Maker Faire Bay Area 2014

Let’s measure the Speed of Light!

DayStart TimeEnd TimeLocationsVideo Coverage
Sunday10:30 AM11:00 AMMake: Live StageNo Video Available

Everyone talks about the speed of light, but hardly anyone every measures it
This is a fun backyard project - we'll use a laser-pointer (the kind you use to annoy cats); a signal generator will switch the beam on and off a million times a second. A piece of glass will split the light into two beams - one goes to a nearby photodiode, the other laser beam bounces off a distant mirror and returns to a second photodiode
Watch the outputs of the two photodiodes on a dual-trace oscilloscope - you can see the difference in arrival times of the two beams. Divide the distance and by the time difference -- and there's the speed o light!



Cliff Stoll

Acme Klein Bottle

Cliff Stoll is an astronomer, writer, Klein bottle maker, and occasionally teaches physics in the east bay. He now works with Newfield Wireless, creators of amazing network analysis software.