How to measure the speed of sound with two lumps of wood ...
4 Steps

## Step 1: The idea

Speed is how far something travels in a known time speed = distance / time.

In everyday life, speed is generally measured in either miles per hour (or kilometres per hour; most of the world is metric). Higher speeds, especially in a scientific or engineering context, are usually measured in metres per second (m/s, ms-1), and that is what we will use in this Instructable.

We will measure the time it takes for sound to travel a known distance by using rhythmic echoes.
oaxacamatt says: Jan 28, 2012. 7:44 AM
Great experiment! Just up the right thing for 10 yr olds I would think too. Bang stuff, listen for the noises then time it. what could be more fun.
rimar2000 says: Nov 19, 2011. 12:44 PM
Very interesting!
Murdok says: Aug 5, 2007. 12:42 AM
I tried this and got a hernia...do you have to use lumber? *Couldn't resist; saw someone else up there make "wood" joke.
!Andrew_Modder! says: Jun 15, 2007. 2:49 PM
heh... wood
Kiteman (author) says: Jun 14, 2007. 3:35 PM
Hey, Eric, happy now?
JakeTobak says: Jun 14, 2007. 9:35 PM
When I saw this I just thought, "Man, where's that guy with the professor avatar. He was talking about this just a couple days ago."
Kiteman (author) says: Jun 15, 2007. 6:49 AM
ewilhelmsays:
How long do you think you can get away with having a comment like this and no Instructable showing us how?

http://www.instructables.com/id/EMKL272F271V6PP/

ewilhelm says: Jun 15, 2007. 10:54 AM
You'll notice me proudly in the "They Like It" box. I like the rhythm aspect of the project to deal with short time durations.
Kiteman (author) says: Jun 15, 2007. 11:01 AM
>smug grin<
trebuchet03 says: Jun 15, 2007. 1:54 AM
I remember doing this in high school :) Nice work :)
lemonie says: Jun 14, 2007. 3:53 PM
Yea, we did this at school! Think it was two planks, and we had a good, big, brick, Comprehensive wall. L