Speed of light

A race to compare the speed of light to other things A quick comparison of how far things can

go in 1 second.Start

Fastest AthletesCheetahFastballDrag racerBulletSupersonic JetCrack of thunderFlash of lightning

10 m25 m

45 m

Most are still going

Drag Racer 175 m

Bullet (still going)

Supersonic Jet (still going)

Crack of thunder

Flash of lightning

We will continue these throughout the presentation!They are roughly to scale.

Astronomical Distances Light takes 8 minutes to get from the Sun to the

Earth. It takes 4 years to get here from the next nearest

star aside from the sun, Proxima Centauri which is 4 light years away.

Light year-The distance light travels in one year 9.5 x1015 m (a really big distance)

Space travel problems

Since we can’t even get close to the speed of light deep space travel would take extreme amounts of time.

crack of thunder (340 m)

Looking into the past Every time you look at the stars you are

looking at the distant past. If you see a star that was 100 light years

away blow up (supernova) it actually blew up 100 years ago.

It just took the light that long to get to you.

Speed of light in things other than a vacuum Whenever light hits a medium it slows it

down. The more dense the material the slower

light can travel. Therefore light tends to travel faster in a

gas, and slowest in a solid. It travels fastest in a vacuum (nothing)

Speed of light in different substances

Bullet (780 m)

Vacuum 2.99792458 x 108 m/s

Air 2.9970 x 108 m/s

Water 2.26 x 108 m/s

Glass 1.97 x 108 m/s

Diamond 1.24 x 108 m/s

It may slow down but… It is still unbelievably fast compared to

everything else. You can not travel faster than the speed of

light. Several interesting things happen when you get close.

Supersonic Jet (900 m)

How far will that light go

If I had 15,000 more slides just like this one, I could cover the distance light would travel (300,000,000 m)