are overflowing with stale peeps. Now you could eat those peeps OR you could

use them to calculate the speed of light. "Finding the Speed of Light ... With Peeps!"

The speed of light is one of those numbers that people have chased for centuries.

Galileo wanted to figure out how fast light moves

"Buona notte" So he proposed an experiment

"Facciamolo!" He would uncover a lantern, and when the light

reached his assistant The assistant would quickly uncover his own

lantern. Using a water clock, Galileo would keep track

of the time between uncovering his light, and seeing his assistant's light.

Up close there was no noticeable delay except for the split second it took his assistant

to react. Then, they started moving away from each other.

Galileo figured the delay would get longer and longer

because the light would need more time to travel the greater distance

But even when they were a mile apart, there wasn't a noticeable pause.

"Che rabbia!" He couldn't have guessed that light had made

the trip in 1 hundred thousandth of a second.

Centuries later, in 1849, a French scientist whose name I can't pronounce

"Armand Hippolyte Louis Fizeau" Came up with an even better way to measure

the speed of light Which was pretty impressive considering that

people weren't even using lightbulbs yet. He took a toothed wheel

and spun it faster and faster He shot a beam of light between the teeth

[PEW] and reflected that beam of light off a mirror

5 miles away [BOING]

By the time the light got back a tiny fraction of a second later, the teeth had moved over

just enough to block the light. BONK PEW BOING BONK

No light made back through But if he made the wheel spin a little faster,

PEW BOING the teeth would move over one position and

the light could get through So when "Fizeau" saw the light he knew the

wheel was spinning so fast that a single tooth was moving over one place in the time it took

light to travel 10 miles. With some quick math

"Armand Hippolyte Louis Fizeau" determined that the speed of light was 700,000,000

miles per hour wHICH WE NOW KNOW WAS ONLY 5% OFF THE Actual

VALUE

Today I can find the speed of light in my Kitchen

Which brings us back to the peeps "Finding the Speed of Light ... With Peeps!"

And a microwave And just a little bit of physics

Microwaves travel at the speed of light And like all waves, their speed is determined

by how fast they go up and down - that's the frequency

And their wavelength

The frequency is written on the side of my microwave ... right here 2450 MHz

so we've go the frequency To calculate the speed we just need to know

the wavelength. and we can find the wavelength by microwaving

peeps I'll set it on low so the peeps don't just

explode

And let it run for a minute or two. Inside microwaves are bouncing around. In some spots

there isn't much energy at all, and the peeps in those area stay cold.

In other spots there's lots of energy and the peeps get really hot

Those hot spots are half a wavelength apart So in theory if I measure the distance between

melted peeps I can find the wavelength

Sure enough some of the peeps are really gooey, while others haven't melted at all

Poking around, I found the rough location of a handful of hotspots

And measured the distance between them... Those average out to 2.43 inches - so that's

half a wavelength - so multiply by 2 so the wavelenght is 4.86 inches

So now to find the speed of the microwaves - which IS the speed of light - I just have

to do the math Frequency times wavelength - 2450 MHz times

4.86 inches Gives us about 12 billion inches per second

- or ... 676,534,091 mph

and that's pretty close to the actaul speed of light

"We Just Found The Speed of Light ... With Peeps!"