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Mathematics

Modelo de desintegración radiactiva

Sustituye monedas por radiación.

Cooking Conversion Calculator

Use this calculator to convert between measurement systems.

Lightning bolts, river deltas, tree branches, and coastlines are all examples of patterns in nature called fractals. In this Snack, you get a striking hands-on introduction to fractal patterns and how they’re formed.

Pi Toss - Science Snack Activity

Asked to get an estimate for the famed mathematical constant pi (π), try the random tossing of toothpicks.

Pi Toss

This video describes the interaction at the exhibit Pi Toss, which uses a statistical technique called "Buffon's Needle" to calculate pi.

Pi Shrine

This circular piece of Exploratorium history has held pride of place in π Day festivities since 1988.

Prince of Pi

Meet Exploratorium physicist Larry Shaw, the originator of Pi Day.

Science activity using straight lines to learn about circles

Pi Graph

Use straight lines to learn about circles.

Science activity to demonstrate pi using circumference and string

Cutting Pi

String and scissors are all you need to find pi all around you.

Pi Has Your Number

Use a touchscreen to search for any number hidden in the first 3 million digits of pi.

Square Wheel

A square wheel can roll smoothly—if the "road" is the right shape.

Café Wall Illusion

These tiles aren't really crooked–they just look that way.