A Research Guide for Students by I Lee

Virtual Library of Useful URLs
Arranged by Dewey Decimal Classification

500-539 Natural Sciences and Mathematics

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500 General science, science museums
500.2 Physical sciences
502.8 Microscopes
503 Science - Encyclopedias, Science - Dictionaries
507 Science - Experiments, (Scientific experiments)
507.8 Science projects, (Science fair projects), (School science projects), (Science exhibition projects)
508 Natural history
509.2 Scientists, (Astronomers), (Biologists), (Chemists), (Geologists), (Mathematicians), (Naturalists), (Physicists)
510 Mathematics
510.28 Calculators
510.7808 Microsoft PowerPoint (Computer file)
512 Algebra, Number theory, Group theory, (Fibonacci numbers)
513 Roman numerals, Writing of numerals
513.028 Abacus
520 Astronomy
523 Solar system, Asteroids, Planets, Stars, Sun, Meteorites, Galaxies, Milky Way, (Moon), (Solar eclipses), (Lunar eclipses)
525 Earth
527 Latitude, Longitude, Nautical astronomy
529 Time, Days, Night, Week, Months, Calendars, Chronology
530 Physics
530.8 Measurement, Weights and measures, Metric system, Volume (Cubic content), (Cubic measurement), (Conversions)
535 Optics, Light
535.86 Kaleidoscopes
538.768 Auroras, (Aurora borealis), (Northern lights)
539.7 Radioactivity, Atomic theory, (Radioactive substances), (Radiation)
540 Chemistry, Chemicals
540.1 Alchemy, (Hermetic art and philosophy), (Transmutation of metals), (Philosophers' stone)
546 Chemical elements
551 Icebergs, Glaciers, (Ice caps), (Ice sheets), Landforms, Geomorphology, Physical geography
551.21 Volcanoes, (Eruptions)
551.22 Earthquakes, (Seismography), (Seismology)
551.4 Water, Physical geography, Natural monuments, Landforms, Earth sciences
551.44 Caves, Cave diving, (Caves and Caverns)
551.46 Ocean, Oceanography, (Oceans), (Sea)
551.47 Tsunamis, Ocean waves, (Earthquake sea waves), (Seismic sea waves), (Tidal waves, Seismic)
551.489 Floods (hydrology)
551.5 Meteorology
551.55 Hurricanes, Cyclones, Storms, Tornadoes, Typhoons, (Winds), (Twisters)
551.56 Lightning
551.6 Weather, Weather forecasting
553.8 Diamonds, Precious stones, (Gemstones), (Jewels)
560 Fossils, Prehistoric animals, Extinct animals, (Paleontology)
567.9 Dinosaurs, Fossil reptiles
570 Biology, Life sciences
572.8 Genetic code, Gene mapping, Recombinant DNA, (Genome mapping), (Genetics), (Genetic disorders)
574.5 Endangered species, (Rare animals), (Wildlife conservation)
574.87 Cells, DNA, Protoplasm, (D.N.A.), (Deoxyribonucleic acid), (Desoxyribonucleic acid)
576.8 Evolution, (Darwinism), (Origin of species), Mutation (Biology), Natural selection
579 Microbiology
580 Plants, Botany
581.1 Photosynthesis
582.13 Flowers, (Roses)
582.16 Trees
590 Animals
590.72 Aquariums, Aquarium fishes, Aquarium plants, Aquariums - Equipment and supplies
590.73 Zoos
591.77 Marine animals (Aquatic animals), (Marine fauna), (Marine zoology), (Sea animals), (Water animals), (Marine mammals)
595.7 Insects
595.78 Butterflies, Moths
597 Fishes, Sharks, Rays (Fish)
597.8 Amphibians, Frogs, (Toads)
597.9 Reptiles, (Turtles), (Lizards), (Alligators), (Crocodiles), (Snakes)
598 Birds
598.47 Penguins
599 Mammals
599.9 Anthropology, Human origins, (Hominids), (Origin of man), (Human paleontology), Physical anthropology, (Biological anthropoloy)

500 General science, Science museums

101science.com. Science learning center. Topics include: Amateur Radio, Biology, Chemistry, DNA Tutorial, Electronics, Mathematics, Microscopy, Micro-Photos, Photography, Physics, Radio, Astronomy, Robots, Science News, Space-Astronomy, and Transistors.

Access Excellence from The National Health Museum. Site for Health and Bioscience Teachers and Learners. Categories include: What's New (Science Updates), About Biotech, Classrooms of the 21st Century, Resource Center (Visual Library, Science and Math, Just for Students, Health Headquarters, News, Activities), and more.

BrainPOP.com - Science: How the World Works. Pick a movie to watch. While waiting for the movie to load, play the quiz game. Movie topics include: Atmosphere, Atoms, Batteries, Big Bang, Crystals, Desert, Dinosaurs, Eclipse, Electricity, Food Chain, Fossil Fuels, Gravity, Heat, Hurricanes, Insects, Jupiter, Land Biomes, Light, Magnetism, Moon, Natural Selection, Ozone, Periodic Table, Photosynthesis, Plate Tectonics, Rainbow, Rainforest, Relativity, Rock Cycle, Saturn, Seasons, Solar System, Sound, Sun, Temperature, Thunderstorm, Tornadoes, Tundra, Volcano, Water Cycle, Waves, Wind, and more.

leaf CBC Health and Science News.

Discover - Science, Technology, and The Future. Current and recent issues of Discover magazine, archive, science news, feature story, web picks, ask Discover, brain works, gallery, search the site.

Do It Yourself Science by by Emily Helliwell, Dec. 17, 2015.
Programs, Activities & Events: Discover the exciting learning opportunities offered by the California Science Center!
Exhibits. The California Science Center offers fun and informative exhibits presented in interactive worlds.

Easy Science for Kids. Categories include: Animals, Plants, Human Body, Earth Science, Technology, Biographies, Fun Activities.

Eric Weisstein's World of Astronomy, Scientific Biography, Chemistry, Mathematics, and Physics. ASTRONOMY includes Atmospheres, Calendars, Solar Systems, Stars, etc.; Search the BIOGRAPHY of a Scientist under Branch of Science, Gender/Minority Status, Historical Periods, Nationality, or Prize Winners; CHEMISTRY includes Chemical Reactions, Geology, Inorganic and Organic Chemistry, etc.; MATHEMATICS include Algebra, Calculus, etc.' and PHYSICS includes Astrophysics, Electromagnetism, Experimental Physics, Mechanics, Optics, States of Matter, Thermodynamics, Wave Motion, etc.

Everyday Mysteries: Fun Science Facts from the Library of Congress. All of the questions presented on this Web site were asked by researchers and answered by librarians from the Library's Science Reference Services. In addition, you are introduced to the Library of Congress' rich collections in science and technology.

The Exploratorium. A museum of science, art, and human perception located in San Francisco, CA. Includes over 10,000 Web pages and hundreds of sound and video files. Focus is on investigating science.

Facts Encyclopedia: Science and Technology from refdesk.com. A-Z list of science resources on the Internet.

Glossary of Scientific Terms from Jefferson Lab, Science Education. See also:
Quick Reference: Glossary of Scientific Terms.
Glossary of Scientific Terms - Definitions and explanations of technical terms from science and philosophy.
Glossary - Science Terms from Visionlearning, a free resource for the study of science, technology and math (STEM).
Science Vocabulary Word List from Enchanted Learning.

High-tech contact lenses are straight out of science fiction - and may replace smartphones by Bishakh Rout, PhD student, Chemical Engineering, McGill University, April 26, 2021. "Contact lenses are the result of an accidental discovery made during the Second World War. Ophthalmologist Harold Ridley noticed that despite acrylic plastic shrapnel shards becoming embedded in the eyes of fighter pilots, it did not appear to cause any harm. This finding eventually led to the creation of hard intraocular lenses for the treatment of cataracts.

... And now, research bringing together chemistry, biology and microelectronics is resulting in contact lenses that are straight out of science fiction ... California-based tech start-up Mojo Vision is working on contact lenses with an inbuilt LCD display, which opens up enormous possibilities. Similar to a head-up display projected on a car's windshield, the contact lens can provide a wide range of information, from phone notifications, map directions and more."

Internet Public Library: Science and Technology. Selected resources on the natural and physical sciences and their practical applications.

K-12 STEM Resources from Tulane University, School of Science and Engineering.
For Your Classroom. Teacher Resources and Classroom Activities.
Tulane STEM at Home. Activities include: Chemistry, Computer Science, Engineering Design and Physics, Life and Environmental Science, Math, Additional Activities.

LiveScience - Strange News.

News in Science from Australia. Contents: All Science News, Health & Medical, Environment & Nature, Space & Astronomy, Ancient Worlds, and Innovation & Technology.

Resources for the History of Physics & Allied Fields. Contents: History of Physics, People (Nobel Prizes in Physics, Notable Geophysicists, Contributions of Women, Physicists on the Money (banknote), Albert Einstein, Andrei Sakharov, etc.), History of Astronomy/Space Science/Geophysics, History of Institutions (mainly physics), Photo Archives, General History - General Physics, History of Science Links, History of Science Community, and Archival Resources (U.S., UK, Europe, Russia, Australia).

Scale of the Universe 2 by Cary Huang. Technical support by Michael Huang. Music "Frozen Star" by Kevin MacLeod. Available in many languages. Zoom from the edge of the universe to the quantum foam of spacetime and learn about everything in between. How to view: Move scroll bar left to zoom in, right to zoom out. Start screen (scroll bar in center position) shows where Human is. Click on object to learn more. Measurements in metric ranging from yoctometers to meters, plus light-years where appropriate. Amazing site.

ScienceDaily. Science Daily Magazine provides news about the latest discoveries and hottest research projects in everything science from astrophysics to zoology. The Breaking News page is updated every 15 minutes. Browse News by Topics. Includes a number of science Encyclopedias.

Science & Nature from BBC. Contents include Animals, Prehistoric Life, Human Body & Mind, Genes, Space, Hot Topics, TV & Radio Follow-up.

Science Engineering and Technology Timeline from Intute - predecessor sites (EEVL, GEsource and PSIgate) together make up Intute.

Science.gov is a gateway to over 50 million pages of authoritative selected science information provided by U.S. government agencies.

Science News for Kids. Categories covered in Article Archive: Agriculture, Animals, Behavior, Chemistry and Materials, Computers, Dinosaurs and Fossils, Earth, Environment, Finding the Past, Food and Nutrition, Human Body, Mathematics, Physics, Plants, Space and Astronomy, Technology and Engineering, Transportation, and Weather.

Science Q & A from New York Times.

Scientific American. Each month, at least two major articles in their entirety are included in the current issue. Each week breaking news stories are tracked and links provided to related sites. Features: Interview (with scientists), Ask the Experts, Bookmarks, Explore! Past issues, Marketplace and more.

Scientific American: Science & Technology Web Awards 2005. 25 favorite sites selected by Scientific American editors. See also archives of best sci/tech sites from 2004, 2003, 2002, and 2001.

Try Science. Gateway to experience contemporary science and technology through interactivity with 400 science and technology centers worldwide.

500.2 Physical sciences

Intute: Science, Engineering and Technology. A free online service providing access to the very best Web resources for education and research, evaluated and selected by a network of subject specialists. Covers physical sciences, engineering, computing, geography, mathematics and environmental science. Database currently contains 33203 records.

Physical science from Wikipedia, the free encyclopedia. Contents include: Basic principles of the physical sciences: Basic principles of astronomy, Basic principles of chemistry, Basic principles of earth science, Basic principles of physics. Notable physical scientists.

The Physical Sciences Resource Center from American Association of Physics Teachers. Browse Resources by subject, grade, and/or type.

502.8 Microscopes

Dennis Kunkel Microscopy. Scientific Stock Photography Through the Microscope. Image gallery, most wanted bugs, about microscopy.

How Do Microscopes Work? from Spike's Science Projects.

How Light Microscopes Work: The Basics, Image Quality, Types of Microscopy, Fluorescence Microscopy ... by Craig C. Freudenrich, Ph.D. - from How Stuff Works.

History of the Microscope. How the light microscope evolved by Mary Bellis, from About.com Inventors.

Microscope Reviews - Helping You Choose the Right Microscope by Jerry Adams, 12 Oct 2018. Site includes: Guide to Buying Your First Microscope; How to Use a Microscope - Step by Step Guide; Parts of a Microscope - The Comprehensive Guide; Basic Guide to Preparing Microscope Slides; Calibrating a Microscope; Microscope Glossary of Terms: Microscope A-Z; Types of Microscopes; Microscope Brands: Zeiss, Olympus, Leica, Celestron; Best Microscope Cameras Reviews & Buyers Guide. Note: Microscopespot.com is a participant in the Amazon Services LLC Associates Program.

503 Science - Encyclopedias, Science - Dictionaries

Earth Sciences, Materials Science, Physical Science from Britannica.

507 Science - Experiments, (Scientific experiments)

Science Activities and Experiments from Education.com. Arranged By Grade, By Subject, By Topic, By Standard.

Science Experiments You Can Do. Simple experiments include: making a lumia box, chemical volcano, slime, sound experiments, dry ice experiments, laser activities, animation devices, and others.

Science Made Simple. Science Projects for Children, Science Help for Parents: What is static electricity? Why is the sky blue? and other elementary school science projects and experiments.

507.8 Science projects, (Science fair projects), (School science projects), (Science exhibition projects)

Agricultural Ideas for Science Fair Projects. Archived site. No longer updated.
Student Science Project from United States Department of Agriculture (USDA) Agricultural Research Service.

Biology Science Fair Project Ideas: Animal Projects from About.com.

Science Fair Central from DiscoverySchool.com. Includes Science Fair Project Ideas.

Science Fair Project Resource Guide from Internet Public Library, IPL Kidspace.

Science Fair Projects World. Illustrated Science Fair Ideas for Elementary, Middle & High School Projects. Categories: Biology (currently empty), Chemistry, Physics, Math, Technology, Human Body.

Super Science Fair Projects. Guide to projects, topics, experiments and ideas. Includes a Step-by-Step Outline and links.

The Ultimate Science Fair Resource. Guide for students on how to do science fair projects. Includes: Project Steps, Hints, Scientific Method, Writing Reports, and Display Boards. Resources include: Idea Bank, Idea Board, and links to Science Research of the WWW.

Yahoo Kids! Directory: Science Fairs.

508 Natural history

American Museum of Natural History. Numerous color photographs from research expeditions by scientists from AMNH. Explore show cases, visit fossil halls, mammal halls, biodiversity, bird halls, and other halls. View virtual diorama of Bison & Pronghorn. Includes an extensive search engine.

509.2 Scientists, (Astronomers), (Biologists), (Chemists), (Geologists), (Mathematicians), (Naturalists), (Physicists)

4000 Years of Women in Science Biography Listing in alphabetical order by last names. See also Listing by Century of Birth, and Listing by Discipline.

Biographies. The Scientists.

Eric Weisstein's World of Scientific Biography. Scientists include: Astronomers, Biochemists, Biologists, Chemists, Engineers, Geneticists, Geologists, Mathematicians, Microbiologists, Physicians, Physicists, Physiologists, and others.

Famous Physicists and Astronomers. Including: Nicolaus Copernicus, Marie Curie, Albert Einstein, Michael Faraday, Stephen Hawking, Edwin Powell Hubble, Sir Isaac Newton, Blaise Pascal, Wilhelm Conrad Roentgen, and others.

Gallery of Scientists. FABBS's "In Honor of ..." program recognizes eminent, senior scientists who have made important and lasting contributions to the sciences of mind, brain, and behavior.

Newton's Castle. Explore this site to learn about Sir Isaac Newton's discoveries and secret life. Learn about color, optical illusions, observations from nature and fascinating facts about how cars roll up hill and why dogs chase cars. Try this short Quiz - Correct responses and explanations provided after you submit your test answers.

People and Discoveries: A Science Odyssey from PBS. Contents: Frederick Banting (developer of insulin), Christiaan Barnard (pioneering heart-transplant surgeon), Charles Best (co-developer of insulin), Niels Bohr (atomic physicist), Francis Crick (solver of the puzzle of DNA), Alexander Fleming (discoverer of penicillin), Abraham Maslow (theorist of humanistic psychology), Grace Murray Hopper (developer of computer language), Guglielmo Marconi (radio transmission pioneer), J. Robert Oppenheimer (atomic physicist and theoritician of astronomical phenomena), Ivan Pavlov (investigator of animal behavior), and others.

Scientific Identity: A Smithsonian Institution Libraries Digital Collection. Portraits of scientists from the Dibner Library of the History of Science and Technology. Browse Alphabetically by Scientists' Last Names, Select a Specific Scientist, Keyword Search of Scientist Names, or Browse by Research Discipline: Aeronautics - Zoology.

510 Mathematics

The ABC of Mathematics: Mathematics Dictionary & Glossary for students from Tuition.com.hk. A comprehensive source of mathematic- related terms. Site contains over 2,000 defined words, terms and concepts, all of which are cross-referenced with live linking. This dictionary has been specifically developed to help students and educators alike, and it is ideal for supporting secondary school and early tertiary students who are studying mathematics or math-related subjects.

AllMath.com. Site provides Math Tools (Flash Cards, Metric Converter), Math Games, Math Reference Pages (Biographies, Glossary, Multiplication Table), Resources, e.g. Career Exploration, Math Humor, Algebra, Calculus, Geometry, Trigonometry, Lesson Plans and Tutorial.

Angle Converter from Periodni.com.
Concert Numbers to Different Number Systems. Convert a decimal number to hexadecimal (binary, octal, ...) and vice versa.
Scientific Calculator for Chemists.
Angle Converter
Angle Converter

Ask Dr. Math. Have a K-12 math question? A Math Forum Project, Dr. Math is staffed by math students at Swarthmore College. A searchable archive of questions/answers is available by level, topic and summaries.

Biographies - Mathematical astronomy from School of Mathematics and Statistics, University of St. Andrews, Scotland.
Indexes of Biographies - Alphabetical indexes and Chronological indexes (-500 AD to 1957)
● Other Biographies Categories include: African mathematics, Ancient Islamic mathematics, Ancient Greek mathematics, Ancient Indian mathematics, and Female Mathematicians
Full Chronological Biographies Index from (1680 BC - 1620 BC) Ahmes to (1984 - ) Qëndrim Gashi.

BODMAS Google image from https://byjus.com/free-gmat-prep/gmat-maths-pemdas-pedmas-bodmas-rules/
Image source: byjus.com

BODMAS Explained - Order of Mathematical Operations from The Calculator Site. BODMAS is an acronym that represents the order of mathematical operations. When a sum contains multiple numbers and operations, you need to know which part to solve first in order to solve it in the correct order. See also: PEMDAS: acronym that helps you remember the order of math operations (parenthesis, exponents, multiplication, division, addition, subtraction).

BODMAS stands for
Brackets (any part contained in brackets comes first)
Order (operations containing powers or square roots)

About BODMAS, from The Calculator Site: "In 2012, Dr Peter Price, co-founder of the Classroom Professor website, posted a mathematical question on his Facebook page. This is what he asked: Can you answer this? 7 - 1 x 0 + 3 ÷ 3 = ? The post quickly spread around Facebook, with over 70,000 people seeing the post and 6,000 people leaving answers and comments. After 2 weeks, Peter pulled together the results - results that surprised him. Only 26% of respondents gave the correct answer (the correct answer is 8)."

Cardinal, Ordinal, and Nominal Numbers from Fact Monster. A cardinal number tells "how many." Ordinal numbers tell the order of things in a set - first, second, third, etc. A nominal number names something - a telephone number, a player on a team.

CuriousMath.com: Math is an attitude. Site contains fun and fascinating math tricks and trivia.

EqWorld - The World of Mathematical Equations. Extensive information on algebraic, ordinary differential, partial differential (mathematical physics), integral, functional, and other mathematical equations. Outlines exact solutions and some methods for solving equations, includes interesting articles, links to math websites, useful handbooks, textbooks, journals, etc. Site contains over 1200 web pages.

Flash Fabrica from Japan. Test your memory and find out how old is your brain. Click "START"; Wait for countdown 3, 2, 1; Memorize positions of numbers; Click circles from SMALLEST to BIGGEST number. Computer will tell you the age of your brain.

History of Mathematics. Includes links to Euclid's Elements, and Chronological List of Mathematicians.

Illustrated Mathematics Dictionary. Math Is Fun. Browse math topic dictionary A-Z. 911 Definitions, 886 Illustrated, 223 Animated.

Is it Magic or Is it Maths? From NRICH - enriching mathematics.

Logic behind Arabic Numbers by Steve Theodore, Antiquarian, from Quora. "Although we call them 'Arabic' numerals, since they reached Europe via Arab culture in the the ninth or tenth centuries, the symbols were originally from India." And from Bhuvi Gupta, Indian Institute of Technology, Kanpur, who duplicated the images originally from "Logic behind Arabic Numbers". The number of angles gives meaning to each letters. Number 1 has one angle. Number 2 has two angles. Number 3 has three angles ... and so on. Observe the letter Zero. It has no angles.

Math.com: The World of Math Online. Basic Math, Everyday Math, Pre-Algebra, Algebra, Geometry, Trigonometry, Statistics, Calculus, and more.

Math for Everyone. Everyday Math (Figuring a Tip at a Restaurant, Sale Price, Wind Chill Factor Calculator, Count Coins, Lottery Odds Calculator), Personal Finance (Simple Interest Calculator, Compound Interest Calculator, Retirement, Amortization Schedule for Loan), Units Conversion (Length, Mass, Area, Volume, Speed, Power, Temperature Conversion: °F, °C, and K), Math @ Home (Cost of Electricity). Site also includes: General Math, K-8 Math, Algebra, Plots & Geometry, Trig. & Calculus.

Math Resources from ProWritingPartner.com. These resources help you realize that Math is easier than you think. Site lists some of the best online math resources for Elementary School Students, for High School Students, and for College and Beyond.

Math Study Guides from SparkNotes.

Math Worksheets from DadsWorksheets.com. One amazing site complete with Answer Key where applicable. Include: Core Math Worksheets (Addition, Subtraction, Multiplication, Division, Fact Family, Long Division, Negative Numbers, Exponents, Order of Operations), Fraction Worksheets, Word Problems, Investing, Roman Numerals, Percentages, Factorization, Mean, Median, Range, Pre-Algebra, Basic Geometry, Telling Analog Time, Analog Elapsed Time, Greater Than and Less Than, Standard, Expanded, Word Form, Rounding Numbers, Ordering Numbers, Measurement & Conversions, Patterns and Puzzles, Printable Flash Cards, Printables, Place Value Chart, Graph Paper, Math Worksheets by Grade (K-Grade 6).

A Mathematical Chronology. Timeline of mathematics. Site provides brief summaries of historical mathematical achievements from about 30000BC when Palaeolithic peoples in central Europe and France record numbers on bones to 2000 when "Mathematical Challenges of the 21st Century" were proposed.

Mathematics Biographies from AllRefer.com.

Millions and Billions and More (Oh My!). Counting from one thousand 10^3 or 1,000, to one vigintillion 10^63 or 1,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000. Really Big Numbers at MrDowling.com.

Numbers from Fact Monster. Include: Integers, Even and Odd Numbers, Rational and Irrational Numbers, Decimal Places, Prime Numbers, Numerical Prefixes, Mean and Median, Rounding Numbers, First Thousand Digits of Pi, Roman Numerals, and others.

SparkNotes: Math Study Guides. Contents: Prealgebra, Algebra I & II, Precalculus, Calculus AB, Calculus BC I & II, Geometry I, II, & III, plus Trigonometry. Includes a Message Board.

A View from the Back of the Envelope is fundamentally about scale. Contents include: Counting by powers of ten, A million dots on one page, How to simplify a number, Why be approximate? Fermi Questions: Rough quantitative estimates, Scaling the universe to your desktop, Your Body Ruler: A User's Manual and much more. See also Angle Cards - A "business card" for measuring angle and How Big Are Things?

Webmath. Over 100 instant-answer, self-help, math solvers.

510.28 Calculators

See also 530.8 Measurement, ... Conversions

Age Calculator from DadsWorksheets.com. This age calculator allows you to enter your birthday and then it shows you each birthday for the next one hundred years.

Better Ideal Weight Calculations by Steven B. Halls, MD. Enter your Weight, Height, Age and Gender, then Click the Calculate Button.

BMI Calculator. Calculate your BMI using this standard BMI calculator. Body mass index (BMI) is a measure of body fat based on height and weight that applies to both adult men and women.

Body Mass Index Table. BMI Chart. Obesity Guidelines, from National Heart Lung and Blood Institute.

Understanding BMI (Body Mass Index). How to calculate BMI: BMI Equation from Renew Bariatrics, a weight loss surgery practice. "Body Mass Index or BMI is your weight in kilograms, divided by the square of your height in meters. When your BMI is, high, it could be indicating that your body fat is high. This measure of body fat is used in various weight categories to help diagnose health problems linked to body fatness or overall health of a person."

Body Mass Index (BMI) Calculator from Diabetes Canada. How to calculate Body Mass Index. Body Mass Index is a simple calculation using a person's height and weight. The formula is BMI = kg/m2 where kg is a person's weight in kilograms and m2 is their height in metres squared.
A BMI of 25.0 or more is overweight, while the healthy range is 18.5 to 24.9. BMI applies to most adults 18-65 years.

Bloomberg.com Currency Calculator
Mortgage Calculator
Retirement Planner / Calculator
Lease / Buy Calculator
401(k) Calculator.

Calculator.com. Directories: Agricultural, Automobile, Brewing, Clothing, College, Computing, Converters, Cooking, Design, Distance, Engineering, Finance, Fun, Health, Manufacturing, Numeric, Personal, Photography, Pricing, Scientific, Sports, and Time.

Calculator.net. Financial calculators, Weight loss calculators, Math calculators, Pregnancy calculators, Other calculators.

Calculator Site: Percentage Calculators from The Calculator Site. Common uses include calculating the percentage for a given statistic, looking to see how much your assets have increased, or wanting to work out the tip for a restaurant bill.

Calculator Soup. Numerous calculators A-Z, ranging from 1000 Prime Numbers, Acceleration Conversion Calculator, to Word Problems, Yu-Gi-Oh Calculator.

CNN Financial Calculators from CNN Business.
Rate of Return Calculator by Tibor Pal, Feb 14, 2021. Contents: What is rate of return? The rate of return definition. How to calculate rate of return on investment - the rate of return formula. How to apply the rate of return calculator.
Retirement Planner - Financial Calculators. Finance and Investment, Loan/Mortgage, Retirement Calculators, (Retirement Planner - 401k Contribution Calculator, 401k Save the Max Calculator, Retirement Savings Analysis, Retirement Income Analysis, Traditional IRA vs Roth IRA, Required Minimum Distribution, Social Security Estimator, Asset Allocation Calculator, Retirement Calculator, Annuity Calculator), Credit Card, Auto Loan and Lease, Stock Calculators, Miscellaneous Calculators.

Conversion Tables and Instant Measurement Conversion from Convert-me.com. All converters included.
● Basic conversions: Mass and Weight, Distance and Length, Capacity and Volume, Area, Speed, Temperature
● Ancient and Historical: Historical Weight, Historical Length, Historical Volume, Historical Area
● Fuel Economy, Cooking, Food Price, Weight to Volume, Fractions and Percent, Currency Rates, Shoe Sizes
● Engineering: Time, Acceleration, Density, Stress and Pressure, Energy and Work, Power, Force, Circular measure, Angular velocity, Torque, Temperature increment, Flow rate by volume, Flow rate by mass, Illuminance, Radiation, Radioactivity
● Computer storage, Data transfer rate
● List of all supported units, Metric conversion, Imperial vs US Customary
History of measurement:
What units of length were used to measure in ancient times?
How was weight measured?
What about measuring volume?
What was the earliest unified system of measurement?
How was time measured before the modern calendar and clock?

Convert Square Feet to Square Meter.
Convert Square Meter to Square Feet from Ask Numbers.
Other Area Conversions e.g. acre, circular foot, circular inch, football field, hectare, rood, square centimeter, square decimeter, square dekameter, square fathom, square mile, square nanometer, square rod, square yard, etc.

Federal Paycheck Calculator from SmartAsset. Use paycheck calculator to calculate your take home pay per paycheck for both salary and hourly jobs after taking into account federal, state, and local taxes.

Finance Calculator by Paul Lutus, arachnoid.com. These equations solve problems that involve compound interest.

Financial Calculators from DiscoverCI:
The Weighted Average Cost of Capital (WACC) Calculator
The Current Ratio Calculator and Formula
The Inventory Turnover Calculator and Formula
The Accounts Receivable Turnover Calculator and Formula
The Debt to Equity Ratio Calculator and Formula
The Percentage Increase Calculator and Example
The Asset Turnover Calculator and Formula

GIGA Online Calculators, Converters, Random Generators from GIGAcalculator.com. Include:
● Popular online calculators: Percentage Calculator, Interest Calculator, Loan Calculator
Fuel Cost Calculator, Miles per Gallon Calculator
Age Calculator, Date Calculator, Days Calculator, BMI Calculator, Ratio Calculator
Area Calculator, Percent Off Calculator, Discount Calculator, Tip Calculator, VAT Calculator, Time Card Calculator, Calorie Calculator
Mean, Median, Mode Calculator, Exponent Calculator, Fraction Calculator, Volume Calculator, Trigonometry Calculator

● Popular online converters: Metric Converter, Imperial to Metric Converter, Metric to Imperial Converter, Percent to Fraction Converter, Fraction to Percent Converter, Km to Miles Converter, Inches to cm Converter
Height Converter, Length Converter, Area Converter, Volume Converter, Speed Converter, Data Units Converter, Salary Converter, Roman Numerals Converter

● Popular random generators: Random Number Generator, Random Password Generator, Random Color Generator, List Randomizer, Random Team Generator, Random Name Picker.

Good Calculators. Wide variety of free online calculators, including: Salary and Income Tax Calculators, Mortgage Calculators, Retirement Calculators, Depreciation Calculators, Statistics and Analysis Calculators, Date and Time Calculators, Contractor Calculators, Budget Calculators, Loan Calculators, Forex Calculators, Real Function Calculators, Engineering Calculators, Tax Calculators, Volume Calculators, 2D Shape Calculators, 3D Shape Calculator,s Logistics Calculator,s HRM Calculators, Sales and Investments Calculators, Grade and GPA Calculators, Conversion Calculators, Ratio Calculators, Sports and Health Calculators, and more.

Google Guide: Calculator. Tables listing: Basic Arithmetic and Advanced Math: Operator, Function, Example. Units of Measure and Conversions: Types of Units, Examples. Physical Constants: Long Name, Shorthand Notation, Click the Link for the Approximate Value.

Health Calculators from Omni Calculator. Body measurements calculators, Dietary calculators, Metabolic disorders calculators, Fertility & pregnancy calculators, Addiction medicine calculators, Diabetes calculators, Cardiovascular system calculators, Electrolytes & fluids calculators, Urology & nephrology calculators, Hematology calculators, Pediatric calculators, Percentile calculators, Pulmonary calculators, Dosage calculators, General health calculators, Covid-19 vaccine calculators, Other calculators.
Blood Alcohol Estimator from Health Status.
Body Fat Percentage Calculator
Body Mass Index (BMI)
Calories Burned Estimator
Daily Energy Expenditure
Frame Size Calculator
Ideal Weight Calculator
Lose One Pound Calculator
Ovulation Calculator
BMR Calculator - Basal Metabolic Rate
Cost of Smoking Cigarettes Calculator
Target Heart Rate Calculator, and more.

The History of the Calculator from the Abacus all the way to the Smartphone, by Alastair Hazell of The Calculator Site, which contains useful calculation and converter tools for every day use. Alastair is an entrepreneur based in East Sussex in the United Kingdom.

Martindale's Calculators On-Line Center. Excellent site containing over 23,785 calculators, covering thousands of subject areas. One of the best free sites on the Internet.

Medical Calculators, Tools and Tests from Patient.info. Resources include:
Abbreviated Mental Test (AMT)
Alcohol Use Disorders Identification Test (AUDIT)
BMI Calculator
Body Surface Area Calculator (Mosteller)
CAGE Questionnaire
CHA2DS2-VASc Score for Atrial Fibrillation Stroke Risk
Estimated Glomerular Filtration Rate (GFR) Calculator
FRAX® - Fracture Risk Assessment Tool
General Practitioner Assessment of Cognition (GPCOG) Score
Generalised Anxiety Disorder Assessment (GAD-7)
Geriatric Depression Scale (GDS)
Glasgow Coma Scale (GCS)
HAS-BLED Score for Major Bleeding Risk
IAPT Phobia Scale
Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE)
Patient Health Questionnaire (PHQ-9)
Pregnancy (Due Date) Calculator
Six-item Cognitive Impairment Test (6CIT)
Spirometry Calculator
Waist to Hip Ratio
Wells' Criteria for DVT

Metric conversion Tables and Equivalents: Temperature, Weight, Volume from Prairie View A&M University, home of the Panthers, Texas.

Metric-English Converter from Earth Observatory, NASA, Mission: Biomes. Temperature Conversion: °C - °F. Linear Measurement: millimeters (mm), centimeters (cm), meters (m), kilometers (km) - inches (in), feet (ft), yards (yd), miles (mi).

Percentage Calculator.

Robert's Online Option Pricer - Calculator.

Builder's Construction Calculators. Very useful site for home builders. Calculator Directory. Choose Imperial or Metric Calculators. Including: Deck Plan Calculator, Triangle Calculator, Lineal metres ~ Cubic metres Converter, Lineal metres ~ Square metres Converter, Log Volume Cubic Meters, Compond Mitre Calculator + Templates, etc. Site also includes: Calculator How-To Videos, e.g. Timber + Concrete Stair Calculator, Roof Framing Calculator Video, Gazebo Plan Calculator Video, etc.

The SmartStudent Guide to Financial Aid - Calculators. Tools will help you determine how much money you will need for a college education in the United States.

Statistics Calculators from Calculator.net.

World Wide Metric: Conversion Calculators. Excellent instant conversion calculators. Length Conversion Calculator (Millimeters Inches Meter Feet Yards), Weight Conversion Calculator (Kilograms Pounds), Pressure Conversion Calculator (Bar Kg/cm Psi), Volume Conversion Calculator (Liters Fluid Ounces Quarts Gallons), Temperature Conversion Calculator (Celsius Fahrenheit).

510.7808 Microsoft PowerPoint (Computer file)

Free Instructional Guides. FREE tutorials for presentations in PowerPoint format. Including: Adding Music, Sound, Flash, Animation, Movement. How to create a template to use with PowerPoint. Talking Books. Free Clip Art by Phillip Martin.

PowerPoint in the Classroom. Tutorial on how to use PowerPoint, a software tool used to present information in a slide show format. Text, charts, graphs, sound effects and video may be incorporated into presentations. Print version of PowerPoint tutorial available free for non-profit use. Teacher's Guide included.

PowerPoint FAQ. Answers to questions on how to use PowerPoint: Drawing, Pictures & Other Imported Files, Animation and Slide Show, Sound & Video, Printing, Formatting, Saving, Using, Editing & Opening Presentation Files.

512 Algebra, Number theory, Group theory, (Fibonacci numbers)

Fibonacci (c.1175 - c.1240) - mathematician. The Fibonacci sequence and biography of Leonardo Fibonacci. Includes photo of Fibonacci's statue in Pisa.

Fibonacci from Wikipedia.

Fibonacci - Nickname. Full name: Leonardo of Pisa, or Leonardo Pisano in Italian. A brief biographical sketch of Fibonacci, his life, times and mathematical achievements.

Fibonacci Sequence from Math Is Fun. The Fibonacci Sequence is the series of numbers: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, ... The next number is found by adding up the two numbers before it.

Pascal's Triangle by Gary Meisner. The Fibonacci Series is found in Pascal's Triangle.

513 Roman numerals, Writing of numerals

Arabic Numbers & Roman Numerals. Convert Arabic Numbers to Roman Numerals from CalculateMe.com.
Converting Roman Numerals to Arabic Numbers and What are the rules for writing roman numerals? From Periodni.com.
Arabic Numeral / Roman Numeral Date Conversion Chart for the 19th & 20th Centuries from Weplan.com. "The Simple Principle: Roman numerals are mathematically converted to Arabic numerals simply through the assignment of an Arabic numerical value to each letter and calculating a total. Example: M=1000 | D=500 | C=100 | L=50 | X=10 | V=5 | I=1. Therefore: MDCLXVI = 1000 + 500 + 100 + 50 + 10 + 5 + 1 = 1666."

Roman Numerals from Fact Monster. Includes Roman Numeral Challenge. The Challenge: Convert Arabic numbers to Roman numerals or vice versa. Choose your level of difficulty. Answers provided.

Roman Numerals. Conversion to arabic numbers and vice versa, from WhatsMyIP.org.

Roman Numerals and Calendar. Here you can do the conversion by hand and understand how and why Roman numerals and dates are as they are. Includes a Roman Numerals Quiz.

Roman Numerals Chart from DadsWorksheets.com. All charts print on one page with versions for 1-10, 1-100 and 1-1000 with and without rules for Roman Numerals.
Visual Roman Numeral Converter. Enter a Roman numeral and convert it to Arabic numeral.

513.028 Abacus

The Abacus: The Art of Calculating with Beads. Includes History of the abacus from ancient times, Instructions on how to add, substract, multiply and divide on the Lee abacus, 1946 contest held in Tokyo of The Abacus vs.The Electric Calculator (winner: the abacus), Resources for Teachers, FAQ, and more.

520 Astronomy

Astronomy for Kids! from Astronomy.
Astronomy: Our Place in Space from American Museum of Natural History. Astronomy is the study of the Universe and everything in it, including planets, stars, galaxies, comets, and black holes. It's full of huge distances, gigantic sizes, and long periods of time.
Glossary of Astronomy Terms
Explore the universe from home with free, online astronomy courses by Sarah MacFarlane, A&S News, University of Toronto, Faculty of Arts and Science, March 31, 2020. A new series of free, online astronomy courses is set to blast families into outer space.

Astronomy Picture of the Day from NASA, covering 20 June 1995 to present. Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
Astronomy Picture of the Day Archive.
Astronomy Picture of the Day Searchable Archive.
Astronomy Picture of the Day Calendar.
Astronomy Picture of the Day's Educational Links.

523 Solar system, Asteroids, Planets, Stars, Sun, Meteorites, Galaxies, Milky Way, (Moon), (Solar eclipses), (Lunar eclipses)

Galaxy. A fun but informative presentation from Australia with photos from NASA, music by Eric Idel, and animations by Camilla Eriksson. Note: File format SWF = "Small Web Format" or "Shockwave Flash".

How to Get to Mars. YouTube video, 6:33 min.

Is Pluto a Planet? What makes a planet? By Jean-Luc Margot, Department of Astronomy, Cornell University, Ithaca, NY. The International Astronomical Union (IAU), an organization of over 9,000 professional astronomers, is the community of experts that is best suited to provide the definition that we need for "planet".

Lunar and Planetary Sciences from National Space Science Data Center (NSSDC).
Planetary Fact Sheets on the Sun, Mercury, Venus, Earth, Moon, Near Earth Object, Mars, Asteroid, Jupiter, Jovian Satellite, Galilean Satellite, Jovian Rings, Saturn, Saturnian Satellite & Rings, Uranus, Uranian Satellite & Rings, Neptune, Neptunian Satellite & Rings, Pluto, Comet, and Chiron.

Mr. Eclipse.com. The Ultimate Resource for Eclipse Photography. Color photos of eclipses of the sun and the moon. Also includes: Solar eclipses and lunar eclipses for beginners, guide to watching eclipses, and links to other eclipse sites.

Nine Planets. Overview of history, mythology, and current scientific knowledge of the planets, moons and other objects in our solar system. Each page has text and NASA's images, some have sounds and movies. The solar system consists of the Sun; the eight official planets, at least three "dwarf planets", more than 130 satellites of the planets, a large number of small bodies (comets and asteroids), and the interplanetary medium. The inner solar system contains the Sun, Mercury, Venus, Earth and Mars. The planets of the outer solar system are Jupiter, Saturn, Uranus, and Neptune (Pluto is now classified as a dwarf planet).

Solar System Exploration: Planets from NASA. Contents: Our Solar System Overview - Sun, Mercury, Venus, Earth, Earth's Moon, Mars, Asteroids, Meteoroids, Jupiter, Saturn, Uranus, Neptune, Pluto, Comets, Kuiper Belt, Beyond Our Solar System, and more.

Views of the Solar System. Multimedia adventure. Splendid views of the sun, planets, moons, comets, asteroids, and more.

525 Earth

All about Earth. Simple, brightly illustrated, fast facts about planet Earth for young children.

Center for Earth Observation from Yale University. View selected satellite images from North America, South America, Europe, South West Asia, North/Central Asia, South East Asia, Africa, Antarctica, Australia, Global Datasets.

Earth Fact Sheet. Bulk parameters, Orbital parameters, Earth Mean Orbital Elements, Terrestrial Magnetosphere, Terrestrial Atmosphere, Images of Earth, Photo Gallery of Earth, Destination: Earth, plus More Earth Science Data from National Space Science Data Center (NSSDC).

Earth facts from One World - Nations Online. Dry facts about Earth, Terre, Erde, Chikyu, Tierra, Terra, Gaia, or Mother Earth, its location, shape, size, weight, age, satellites, orbital data, rotation, velocity, surface, atmosphere, highest point on surface, symbol, map, life, population, continents, plus statistics for top 50 of the world's most populated cities.

Earth From Space: Smithsonian National Air and Space Museum (Hardcover) by Andrew K. Johnston
Earth From Space:
Smithsonian National Air and Space Museum
by Andrew K. Johnston

The Earth from Space. A Williamson Gallery Virtual Exhibition: Jay Belloli, Curator; Dr. Randii R. Wessen, Science Advisor, from ArtCenter.
Looking at Earth: From 100 miles to 100 million miles. Galleries - Views from Explorer 1, NASA.

Exploring the Planets: Earth from National Air and Space Museum. Contents: One-page Earth facts, Realms of Earth: atmosphere, lithosphere (rocks), hydrosphere (water), biosphere (living things), and magnetosphere (magnetic fields), Exploring Earth from orbit, Mission to Planet Earth, plus an Earth Imagery Index covering images of the Earth from NASA. Also check out: 1301 Florescent Bulbs Lit Solely by Magnetic Fields.

Google Earth lets you fly anywhere on Earth to view satellite imagery, maps, terrain, 3D buildings and even explore galaxies in the Sky.

Pale Blue Dot by Carl Sagan (1934 - 1996). YouTube video, 3:30 min. Published on Mar 24, 2009 by carlsagandotcom. "This excerpt from Carl Sagan's lecture at Cornell University (1994) was inspired by an image taken, at Sagan's suggestion, by Voyager 1 on Feb 14, 1990. From a distance of about 6 billion km, Voyager 1, which had completed its primary mission and was leaving the Solar System, was commanded by NASA to turn its camera around and take one last photo of Earth across a great expanse of space, at the request of Carl Sagan.
The accompanying words, written in 1994 by Carl Sagan, are still very relevant today."

The Seasons, the Equinox, and the Solstices from Weather.gov, US Dept of Commerce, National Oceanic and Atmospheric Administration (NOAA), National Weather Service (NWS), Cleveland, OH. The Equinox (Vernal & Autumnal), The Solstices (Summer & Winter), The Seasons, The Relationship Between Length of Day and Temperature.

TerraServer - USA. Terraserver USA has changed to MSR Maps. TerraServer-USA Web site is one of the world's largest online databases, providing free public access to a vast data store of maps and aerial photographs of the United States. The first three fields, Street, City, and State, enable you to search for an address or a place name in the U.S. only. If you want to search for data in Canada or Mexico, click on the Advanced Find button found in the Top section of each page. You can view TerraServer-USA imagery in 3D at the World Wind site below.

The Whole History of the Earth and Life „ÄźNewest Edition. YouTube video, 1 hr. 5:56 min. Published by Kaoru GreenEmerald, Apr 8, 2020. This is a documentary which portrays the birth of the solar system, the birth of the Earth, and the emergence and evolution of life on Earth depicted through latest research activities. Executive producer: prof. Shigenori Maruyama. Supported by Hadean Bioscience Project. The Origin of the Earth. The formation of the Solar System. The formation of the Earth.

World Wind. Developed at NASA Ames Research Center, World Wind lets you zoom from satellite altitude into any place on Earth. Amazing software provides latitude, longitude and altitude of your chosen location. Free download. Check download requirements of World Wind, e.g. 256 MB of RAM, 3D Graphics Card, 2 GB of disk space, and more.

527 Latitude, Longitude, Nautical astronomy

Astrodienst. Find Geographic Locations with information on their latitudes and longitudes. Enter at least the first few letters of the name of the city (not country) to search for. Answer includes city, province or state, country, latitude and longitude, plus time zone, as well as the exact date and local time where city is located at time of information access, all in relation to Bahji, of course.

Getty Thesaurus of Geographic Names Online (TGN). Latitude and longitude given in most records, minimum record for each place includes a name (English name, vernacular or local-language name), a place type (city, island, etc.), and a position in the hierarchy that shows its parent places - nation (country name, e.g. United States).

Great Circle Distance Calculator. Once you know the Latitude and Longitude of two places (search in Astrodienst above), you can calculate the distance between any two places in the world as the crow flies, i.e. the straight line distance between the two points. Distances are given in kilometers.

How Far Is It? Search distance FROM one location TO another as the crow flies. Results will show not only the distance (in miles, kilometers, and nautical miles) between the two points, but the longitudes and latitudes of the places as well, plus County, Population, and Elevation if it is a place in the U.S.

Latitude and Longitude. Illustrated explanation by Dr. David P. Stern.

Latitude and Longitude Search - United States. Look up the exact location of millions of places in the U.S.

U.S. Gazetteer. The U.S. Gazetteer Files provide a listing of all geographic areas for selected geographic area types. The files include geographic identifier codes, names, area measurements, and representative latitude and longitude coordinates.

View Above Earth. Enter the latitude and longitude of a place you would like to view, then add the altitude in kilometres to indicate the distance you wish to view it from above the earth. If you don't know the latitude or longitude of a place, you can choose a city from Cities around the World. You get a better view if you choose a place that is currently in daylight hours rather than at night time.

529 Time, Days, Night, Week, Months, Calendars, Chronology

Click here for more links on Methods for Measuring Time

Calendar Zone. Calendar related information or types of calendars include: Celestial, Cultural (Aztec, Chinese, Islamic, etc.), Daily, Event, Geographic, Historic, Holidays, Interactive, Millennium, Misc., Reference, Reform, Religious, Software, Traditional, Web, Women, and Y2K. Plus Calendar Quotes & Poetry, Century Prayer (1901), New Calendars, and Calzone Recipes.

Calendars through the Ages. Topics covered: Our 7-day week (origin and meaning of names of days of the week), Our year, Calendars (Christian, Jewish, Islamic, Chinese, Mayan, etc.) plus other unusual and interesting subjects relating to time and calendars.

Clocks and Time. Some 400 Web pages of information dealing with clocks and time. Contents include: Museums, Books, Magazines & Journals, Ezines, Newsgroups & Mailing Lists, Buying & Selling, Organizations & Agencies, Clockmaking & Watchmaking, Education Software, Sundials, History, Time Standards & Setting, and more.

World Clock from The Time Now - A more accessible site for the vision impaired than many other sites.

Free Printable Calendar Templates. Create free printable calendars that are formatted for Microsoft Word ®.

Free Printable Calendars. Free calendars from Printfree.com. Print monthly or yearly calendars.

Local Times Around the World. Select a continent or region: Africa, America, Antarctica, Asia, Atlantic, Australia, Europe, or Pacific. Choose a country and a location to view details, e.g. Geographical Location: (40° 42' N, 74° 0' W), Current Local Time, Greenwich Mean Time (GMT), Coordinated Universal Time (UTC), and Local Time Zone.

On Time: An Exhibition at the National Museum of American History. Explores the changing ways Americans have measured, used, and thought about time from 1700 to now. Requires Macromedia Flash 4 and a fast computer.

Online Current Time. Set new alarm. Alarm Clock. Timer. Stopwatch. Countdown.

Printable Calendars. Printable-Calendar.com is a free service that provides unlimited printable calendar templates in two different formats (Word and PDF). Print calendars for 2004, 2005 or 2006, monthly or yearly.

Time and Frequency Division of the National Institute of Standards and Technology (NIST). Find the Official United States Time. You can set your computer clock to the correct time right now by using the Internet or the Telephone.

Time Travel. Everything you always wanted to know about time travel: Time and the Universe, How to build a time machine, Does time exist? Wormholes, Einstein Connection, Wormhole Engineering, Ultimate Proof, and more.

Time Zone Converter. Apart from allowing you to convert time zones in current time, site also allows you to specify a given date and time to convert past or future times. Select a location "From Time Zone" and convert "To Time Zone" of another location.

A Walk through Time. The Evolution of Time Measurement. Topics covered: Ancient Calendars, Early Clocks, Revolution in Timekeeping, The "Atomic Age", World Time, Scales, National Institute of Standards and Technology (NIST) Time Calibration.

World Time - 36 time zones at a glance. See also Countries and Time Zones and Astronomical Background. Available in German and English.

World Time Server.com. Accurate local time and date in every time zone! Find current time and date anywhere in the world. Search a location by country or by major city.

www.timeanddate.com. Topics covered: Time (World Clock, Search for City, Meeting Planner), Date (Calendar), Counters (countdown to any date of your choice from current date and time), 3rd Millennium, Latest updates.

530 Physics

Albert Einstein - Biography. What Albert Einstein did ... and why you should care, from Shmoop.com.
Other websites on Albert Einstein (1879-1955):
Albert Einstein Archives
Einstein's Big Ideas from PBS - NOVA
The Year of Albert Einstein by Richard Panek, Smithsonian Magazine, June 2005.
Einstein A-Z: Einstein Fun Facts
Albert Einstein - 1,427 pages from Federal Bureau of Investigation (FBI). "An investigation was conducted by the FBI regarding the famous physicist because of his affiliation with the Communist Party. Einstein was a member, sponsor, or affiliated with thirty-four communist fronts between 1937 and 1954. He also served as honorary chairman for three communist organizations."

Look up: Basic Physics from Babylon.com. Physics Dictionaries and Glossaries provide definitions in a wide range of technical fields, including Fiber Optics, Optical Networking Terms, Glossary of Wireless, RF (Radio Frequency) and Microwave Terms, Glossary of liquid chromatographic terms, Gravity/Magnetic Glossary, Solar Physics Glossary.

The Physics Encyclopedia: Physics Internet Resources. Unfortunately, this site is no longer updated.

The Particle Adventure. An award-winning site that allows you to explore the world of fundamental particles and forces and then to investigate the experimental evidence and techniques. Includes links to other physics sites.

The Physics Factbook: An Encyclopedia of Scientific Essays edited by Glenn Elert, written by high school students. Topic Index: acceleration, angular-velocity, area, density, electric-current, electric-field, electric-voltage, electrical-resistivity, energy, force, frequency, friction, length, magnetic-field, mass, money, number, power, pressure, refraction, temperature, time, velocity, volume.

Physics News. Links to News and Information related to Physics. Includes Past News Headlines.

PhysicsWeb. Web link resources on physics around the world.

SparkNotes: Physics Study Guides. Contents: Vectors, Kinematics, Dynamics, Work, Energy and Power, Linear Momentum, Rotational Motion, Oscillations, Gravitation, Thermodynamics, Magnetic Forces and Fields, Optics, and Special Relativity.

What is Physics? From Universal Class. Physics is the science of nature ... which deals with the laws and properties of matter and the forces which act upon them. Quite often, physics concentrates upon the forces having an impact upon matter, that is, gravitation, heat, light, magnetism, electricity, and others.

530.8 Measurement, Weights and measures, Metric system, Volume (Cubic content), (Cubic measurement), (Conversions)

AskNumbers.com. Online conversions between different metrics of length, weight, temperature, pressure, energy, frequency and more.

Celsius to Fahrenheit - Temperature Conversion from Celsius to Fahrenheit. How to calculate manually: Multiply the Celsius temperature by 9/5, then add 32°, e.g. Convert 37° C to Fahrenheit: 37 * 9/5 = 333/5 = 66.6, then: 66.6 + 32 = 98.6° F.
Fahrenheit to Celsius - Temperature Conversion from Fahrenheit to Celsius. How to calculate manually: Subtract 32° to adjust for the offset in the Fahrenheit scale. Multiply the result by 5/9, e.g. Convert 98.6° Fahrenheit to Celsius: 98.6 - 32 = 66.6, then: 66.6 * 5/9 = 333/9 = 37° C. Site also provides a mental math method to approximate the Fahrenheit to Celsius conversion, and vice versa.
See also Measurements from AAA Math - Each page has an explanation, interactive practice and challenge games about measurements.

Conversions from Abbreviations.com. Enter you conversion query, or Select conversion type: Measurements, Number Systems, Time Zones. Weight: Angles, Area, Cooking, Energy, Force, Length, Power, Data, Storage, Time, Temperature, Velocity, Volume. Select What would you like to convert? carat, dram, grain, gram, kilogram, lb, long ton, metric ton, milligram, ounce, pennyweight, pruta, scruple, short ton, stone ton. Enter the Amount you wish to convert to get immediate results.

Convert.net is an online conversions calculator for a wide variety of unit measurements. Example: Enter your natural language conversion query: "Convert 1 cup to teaspoons", click Submit, instant result below will show: 1 cup = 48 teaspoons. Or you can Select conversion type: Measurements, Number Systems, Time Zones and choose your conversion factors.

How Many? A Dictionary of Units of Measurement from ibiblio.org. Cleave Books: Dictionary of Units, FAQ and Other Measures and Specialist Calculators from CleaveBooks.co.uk.

Fahrenheit to Celsius Conversion and vice versa from Metric Conversions.

Interactive Units Converter. Measurements available for conversions include: Weight and Mass, Distance and Length, Capacity and Volume, Area, Speed, Temperature, Time, Pressure, Energy and Work, Circular Measure, and Computer Storage. Plus links to other resources on units conversion such as: Yahoo! list of Online Converters, A Dictionary of Units, Conversion & Calculation Center, Online Conversions, and Maribi.Com Conversion Tables.

Martindale's Calculators On-Line Center contains over 19,000 Calculators, including many Science and Math Calculators.

Measurement Conversions. View Tables of Unit Conversion Factors with over 800 conversion factors, Temperature Conversion (Fahrenheit, Celsius, Kelvin), and Copper Wire Gauge.

Metric Conversions. Metric conversion charts and calculators for metric conversions. Temperature, Weight, Length, Area, Volume, Speed, Time, Angle, Pressure, Energy and Power, Health and Wellbeing. Conversion Tables: Length (feet, meters), Area (square feet, square meters), Mass and Weight (ounces, grams), Liquid Volume (pints, liters), and Temperature (Fahrenheit, Celsius).

MegaConverter 2. Excellent site for Unit Conversions and Calculations. Quickly convert practically everything related to numbers. Links to other existing conversion sites in chemistry, computer, cooking, currency, dress size, engineering, finance, geology, lighting, maps, master clock, Morse code, oceans, ring size, and even shoe size.

metric conversions.org. Online conversion calculators, conversion tables and metric formulas. Temperature conversions, Celsius conversion, Celcius conversion (and other common misspellings), Celsius to Fahrenheit, Measurement conversions, Converting kilometers to miles, Centimeters to inches, Weight conversions, Acre conversion.

Online Calculators, Conversion Tools, Measurements & Weights from OnlineConversion.com.

OnlineConversion.com. Convert just about anything to anything else. Over 5,000 units, and 50,000 conversions including Length / Distance, Temperature, Speed, Volume, Weight / Mass, Computer (Binary Digit Conversion), Date / Time, Cooking, Angles, Area, Power, Energy, Density, Force, Pressure, Astronomical, Numbers, Finance, Miscellaneous, Fun Stuff, Clothing, Light, Torque, Vicosity, Frequency, Flow Rate, and Acceleration.

PDFConverter.com. Free Online Unit Converter for Mass, Time Zone, Area, Angle, Length, Volume, Pressure, Temperature and Data Storage.

Rapid Calculation. Online calculatiors, Tools and Reference. 1. Unit Conversions (Area, Length, Speed, Temperature, Time Conversions). 2. Grade Calculators (College GPA Calculator, Final Grade Calculator, High School GPA Calculator, etc.) 3. Electricity Calculators (Amps to Watts, Amps to Volts, Amps to VA, Amps to kVA, Amps to kW, eV to V, Joules to Watts, Volts to Watts Calculator, Watts to Amps, etc.)

Roman Numerals and Date Converter. Dates in roman numerals conversion calculator. Enter a number or a Roman numeral to convert between Arabic numbers and Roman numerals, and vice versa.

Roman Numerals and Calendar. Here you can do the conversion by hand and understand how and why Roman numerals and dates are as they are. Includes a Roman Numerals Quiz.
Conversion from Indo-Arabic Numerals to Roman 1 - 1449.
Conversion from Arabic Numerals to Roman 1450-2100.
Conversion from Roman Numerals to Arabic 1450-2000.
Roman Numerals: How They Work.
Brief History of Roman Numerals.
Modern Uses of Roman Numerals, and more.

Runner's Web Kilometer / Mile Distance Converter. Widget Distance Converter. Enter miles or kilometers and click on "Calculate" button.

Unit Converter from WhatsMyIP.org. Length, Area, Weight, Speed, Energy, Power, Volume, Time, Temperature, Pressure.

Units Conversion from Rapid Tables. Color conversion, Electric charge conversion, Energy conversion, Frequency conversion, Image conversion, Length conversion, Number conversion, Power conversion, Temperature conversion, Voltage conversion, Weight conversion, Electrical calculation.

535 Optics, Light

Making the most of your mind selfridg Google image from http://www.theschooloflife.com/shop/media/catalog/product/cache/1/image/681x/040ec09b1e35df139433887a97daa66f/m/a/making_the_most_of_your_mind_selfridges_1.jpg

Atmospheric Optics. Light playing on water drops, dust or ice crystals in the atmosphere produces a host of visual spectacles - rainbows, halos, glories, coronas and many more. Includes Links and Resources.

A Brief History of Optics from University of Illinois at Urbana-Champaign (UIUC). Timeline from before 300 B.C. to 1990 A.D.

Causes of Color. "Why are things colored? There are three causes. ... Light is made in the yellow glow of a candle. Light is lost when sunlight filters through stained glass. Light is moved when sky turns crimson sunset. ... all the colors in the universe originate from ... fifteen fundamental physical causes."

Tutorial 8 - Discover how light works in the real world and apply this knowledge to produce simulated light using OpenGL written by staff of OpenGL. 1. The nature of light. Introduction.What light is. A stream of particles or wave of energy? Color of light. Abstract types of light. Ambient light. Diffuse light. Specular light. Emissive light. 2. Light in OpenGL.

Light from Wikipedia.

Light - Physics written by Glenn Stark, from Encyclopedia Britannica.

The Nature of Light from Physics Hypertextbook. Discussion. Summary. Practice. Problems. Resources.

Optics from Wikipedia.

Optics for Kids. Quick answers to questions about light and optics. Topics include: Light Basics, Controlling Light, Lenses, Magnifying Glass: A simple optical device, White Light and Laser Light, and others.

Physics Study Guide / Optics from Wikibooks. "Light is that range of electromagnetic energy that is visible to the human eye, the visible colors."

Science, Optics & You. Excellent site from Florida State University. Activities are designed for students to learn about light, color, and optics. Contents include: Timeline in Optics, Pioneers in Optics, Light and Color, Museum of Microscopy, Optics Resources on the Web, Interactive Java Tutorials, e.g. Optical Illusions, Primary Colors, the amazing Powers of 10, Photo Gallery, Olympus MIC-D Digital Microscope, Teacher Resources, Student Activities, and much more.

535.86 Kaleidoscopes

DIY | How to Make a REAL Kaleidoscope (So Easy!) YouTube video, 3:01 min. Published by WhatsUpMoms, Oct 27, 2017.

Kaleidoskop. YouTube video, 2:04 min. Uploaded on Jul 24, 2011.

How to Make a Kaleidoscope by eHow Contributor.

How to Make a Kaleidoscope by Dr. John Greivenkamp. Professor at University of Arizona College of Optical Sciences, Tucson, AZ. These instructions have been translated into Belorussian by Paul Bukhovko of .

How to Make a Kaleidoscope by Mary Bellis, About.com Guide.

How to Make a Kaleidoscope in 9 Steps from wikiHow. Note: Warnings: "DO NOT look at bright lights with the kaleidoscope, especially a blazing sun. The image will be multiplied nine times and hurt your eyes badly. Not enough to be called an emergency, but it will hurt.
If you do look at the sun with the kaleidoscope, your eyes will blur instantly, and you will see strange color patches cross your eyes for a few minutes. If you continue to look at the sun with the toy, even for more than a couple of seconds, it could damage your eyes permanently."

How to Make a Kaleidoscope - Video 2:36 min. from Howcast. Includes step-by-step instructions in text.

Be Dazzled: Kaleidoscope. How to make a kaleidoscope (Grade 4).

Make Your Own Kaleidoscope (using your own picture) from Karzydad. It really works! Instructions: Find an image you like on the Internet, and paste in the image URL here, then press the load button. Note: it is not enough to use the URL of the page the image is on, you must provide the URL of the image itself (typically ending with .jpg, .gif or .png), e.g. http://www.bydewey.com/tea.jpg. Once your image is loaded which may not be visible, click on one of the three symbols/designs at the upper left side and voilà your kaleidoscope appears.

538.768 Auroras, (Aurora borealis), (Northern lights)

Aurora (astronomy) from Wikipedia, the free encyclopedia.

Aurora Borealis. Images and time lapse movie.

Aurores boráales - Norvàge 2010 . YouTube video, 2:43 min.

The Aurora Page. Information, links and images about the Northern Lights from Michigan Technological University, Department of Geological/Mining Engineering & Sciences.

Auroras: Paintings in the Sky from Exploratorium. Take a Self-Guided Tour to find out What are auroras? What do they look like? What makes them happen? Where can you see them? Why are they different colors? Includes Aurora links, resources, and a teacher's page.

Glow and behold! The 25 best aurora pictures of 2021, from dazzling light shows in Alaska to heavenly displays over Tasmania and New Zealand by Ted Thornhill, MailOnline Travel Editor, DailyMail.co.uk, Dec 10, 2021.

Lapland Auroras. YouTube video, 7:50 min. Excellent collection of Aurora borealis images with some very colorful shots.

Northern Lights. "The bright dancing lights of the aurora are actually collisions between electrically charged particles from the sun that enter the earth's atmosphere. The lights are seen above the magnetic poles of the northern and southern hemispheres. They are known as 'Aurora borealis' in the north and 'Aurora australis' in the south." What causes the northern lights? "Legends of the Lights: 'Aurora borealis', the lights of the northern hemisphere, means 'dawn of the north'. 'Aurora australis' means 'dawn of the south'. In Roman myths, Aurora was the goddess of the dawn."

539.7 Radioactivity, Atomic theory, (Radioactive substances), (Radiation)

The Discovery of Radioactivity: The Dawn of the Nuclear Age by Slowiczek and Peters. See also Radioactivity: Historical Figures: Wilhelm Conrad Roentgen (1845-1923), Antoine Henri Becquerel (1852-1908), Pierre Curie (1859-1906), Marie Curie (1867-1934), and Ernest Rutherford (1871-1937). "During the investigation of radioactivity he [Ernest Rutherford] coined the terms alpha and beta in 1899 to describe the two distinct types of radiation emitted by thorium and uranium." Marie and Pierre Curie and the Discovery of Polonium and Radium by Nanny Fröman.

Historical Instrumentation Collection from Oak Ridge Associated Universities. Contains color photos and images of over 1000 objects: Atomic Movie Posters, Electrometers, Radiation Warning Signs, Electroscopes, Radioactive Quack Cures, Geiger Mueller Detectors, Radioactive Sources, Health Physics Posters, Reactors, Hiroshima and Trinity, Shoe Fitting Fluoroscope, Ionization Chambers, X-ray and Gas Discharge Tubes, and others.

Marie Curie from Wikipedia, the free encyclopedia.
Marie Curie Biography - Marie Curie: The Nobel Prize in Physics 1903.
Marie Curie: Facts & Biography by Mary Bagley, LiveScience Contributor.
Marie Curie on Curiosity, Wonder, and the Spirit of Adventure in Science by Maria Popova.
Marie Curie's Passion by Julie Des Jardins, Smithsonian Magazine.
Madame Curie: A Biography by Eve Curie, Translated by Vincent Sheean.

Natural Radioactivity. Fact sheet. See also Radioactivity in Nature.

Radiation and Radioactivity from Idaho State University. Contents: Radiation and Radioactivity, The Atom, Alpha Radiation, Beta Radiation, Gamma Radiation, X-ray Radiation, Properties of Radiation, Half-Life, Measures of Radiation and Radioactivity, Measurement of Radiation, Gas Filled Detector, Measurement of Radiation, Sodium Iodide Detector, plus Glossary, Radiation and Risk, Radiation and Us.

Radioactivity from Hyper Physics. Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.