Find by Interest Physics &
Math
Anatomy of Photo 51
When you know how to look at it, this shadowy X-ray
photograph speaks volumes about the shape of DNA.
Approximating Pi
Archimedes used a fairly simple geometrical approach to
estimate pi. See how he did it here.
Birth of a Supernova
What exactly happens in a supernova explosion? See
step-by-step the sequence of events that unfold during Type Ia
and Type II supernovae.
Build a Bridge
Learn about the four major types of bridges and match
the right bridge to the right location.
Buoyancy Brainteasers
Why does a helium-filled balloon in a car float forward
when the car accelerates? Find the answers to this and two
other brainteasers.
Construct an Aqueduct
Build an aqueduct that will supply an ancient Roman
city with clean water.
Design a Fractal
Create and save your own wildly colorful fractals using
our generator.
Destroy the Castle
Make adjustments to your trebuchet, then try to destroy
a castle wall.
Drake Equation, The
Try your hand at calculating how many intelligent,
communicating civilizations might be in our galaxy.
E = mc2 Experts
Hear how 10 top physicists describe the equation in a
few minutes or less.
Einstein Quotes
Seven thought-provoking statements from the world's
most famous scientist
Elemental Quiz, An
Take a test you likely never took in chemistry class.
Fire a Torpedo
Find out how a torpedo makes use of a gyroscope as you
try to sink enemy ships.
Floating and Sinking
Find out why hot-air balloons fly.
Force of Impact
How could a lightweight piece of debris cause
catastrophic damage? Find out in this simulation of the
shuttle's launch.
Free-Falling
The force of gravity for astronauts orbiting Earth is
just about the same as it is on our planet's surface. Why,
then, do they float? Find out here.
Galileo Games, The
Test your knowledge with these online experiments
related to Galileo's early work on gravity.
Galileo's Experiments
Conduct virtual versions of Galileo's thought
experiments, including those using an inclined plane and a
pendulum.
Getting Airborne
Send a plane down a runway at top speed and see how it
achieves enough lift to take off.
History of the Universe
Follow the evolution of the universe from the big bang
to the time 10100 years from now when burned-out stars and
black holes will have evaporated.
How Big Were They? (Easter Island Moai)
Compare the weight of the largest moai to a herd of
elephants.
How Big Were They? (Egyptian Obelisk)
Compare the weight of the largest ancient obelisk to a
herd of elephants.
How Many Pearls?
Estimate how many pearls are in a treasure chest.
Lever an Obelisk
Use a lever to raise one end of an obelisk three feet
off the ground.
Lunar Puzzlers
If you're standing on the moon and the Earth is
directly overhead, how long will it take for our planet to
reach the moon's horizon? Take a shot at this and other lunar
brainteasers.
Make the Earth's Weather
What if the Earth's warm spots were a little colder, or
its cold spots a little warmer? What if it were to spin at a
different speed, or if the planet itself were bigger or
smaller? How would our weather change?
Move the Moai
Figure out how to move a moai across Easter Island.
Moving Targets
Follow animations that describe how the Doppler effect
helps astronomers determine whether stars are moving toward or
away from Earth and at what speed.
Multi-Dimensional Math
See for yourself why it's a walk in the park to dream
up extra dimensions, at least for mathematicians.
Outfitting a Fighter Pilot
A pilot's gear is a sophisticated support system that
can save his life in deadly situations.
Play a Virtual Market
Invest in traditional stock or buy and sell call
options with a virtual $100,000.
Power of Tiny Things, The
How much energy does a paper clip pack? Test your
intuition in this quiz.
Pulling Cs and Gs
Find out about centripetal force.
Pythagorean Puzzle
Manipulate a square to see how it fits into the
Pythagorean Theorem.
Reading Maya Hieroglyphs
The Maya invented a writing system so elaborate that
experts have yet to completely decipher it. See if you can
interpret some classic Maya hieroglyphs.
Resonance in Strings
An everyday string and the tiny strings of string
theory have a lot in common. It's all in the vibration.
Scaling the Pyramids
Print out and assemble a scaled-down version of the
Great Pyramid.
See a Reversal
Watch a simulated flip of the Earth's magnetic field,
from the first signs of instability to the final reversal
Send a Coded Message
Use a virtual version of the German ciphering machine,
Enigma, to send an encrypted message.
A Sense of Scale: Absolute Zero
Travel from absolute zero to what may be the highest
temperature.
A Sense of Scale: Hunting the Hidden Dimension
Travel from absolute zero to what may be the highest
temperature.
Simple Cipher, A
Deciphering this secret message isn't all that
difficult—you just need a little time.
Sonic Boom
Learn the basics about a sonic boom.
Sounds Underwater
Test your knowledge of sound and water with these 10
true/false questions.
Sources of Radiation
Explore a landscape and locate radioactive sources both
harmful and beneficial, natural and manmade.
Spin a Spiral Galaxy
Spin a spiral galaxy on two axes, revealing how a
galaxy can appear to be elliptical or round or flat in shape,
depending on your vantage point.
Think Like Einstein
The special theory of relativity isn't all that
difficult to understand, if you follow Einstein's logic.
Time Traveler
Send an astronaut on a round-trip journey to a star and
then compare her age with a person who stayed on Earth.
Tour the Spectrum
Radio waves, microwaves, infrared waves, visible light,
X-rays, and gamma rays are all part of the electromagnetic
spectrum. Get a comprehensive view of all the rays and waves
in this self-guided tour.
Up, Up, and How Far Away?
Use visual perspective to estimate the distance to an
object.
What Causes the Tides
Mostly the moon, somewhat the sun, and naturally the
Earth itself.
Wing Designs
Experiment with airfoil shapes and discover how they
affect the way a plane flies.