physics question?

Question

How do i measure the speed of sound w/o using computer software; instead, using a stopwatch and sharp noise.

Thanks

Answer 1

1) Find a long hallway that will produce a nice echo. (This is the hardest part)

2) Measure the distance from the end of that hallway to where you are standing. This distance is D

3) Produce the sharp noise. (A cap gun would work nicely here)

4) Using the stopwatch, measure the amount of time it take between when you fire the gun and when you hear the echo. This time is T.

5) The speed of sound will be 2*D/T. (the sound had to travel to the end of the hall and back to you)

Be aware that this method has several sources of error, the main one being your reaction time on the stopwatch.

Answer 2

You'll need a helper and a very large, mainly clear, space of land.

Ask your helper to stand a few hundred feet away, and measure the distance between you and him exactly. Then, when you're ready with the stopwatch, ask him to make the sharp noise (obviously it will have to be a very loud noise!) Make sure he indicates when he is making the noise - for example, he could wave when he makes it.
As soon as this signal is made, start the stopwatch. Then listen carefully for the sound and as soon as you hear it stop the stopwatch.

Then you can simply use v=d/t to find out the speed of sound, which is 340m/s.

Answer 3

You answered your own question.

You need an instantaneous signal (light flash, cell phone alert, walkie talkie, etc.) from the origin of the sound (starting gun) to start the stopwatch.

When the actual sound reaches you, stop the stopwatch.

Then divide the distance between you and the origin of the sound by the time elapsed on the watch.

Done!

For the experiment to be practical, a distance of between a half mile and two miles should be used. A half mile is about 2 seconds and two miles is about 8 seconds...easy to manage on a stopwatch. If you are too close, it all happens too fast and the accuracy is off.

Answer 4

Find the biggest canyon that you can find and get a gun. Fire the gun at the same time that you start the watch. When you hear the echo come back then stop the watch. Then measure the distance to the reflecting side remembering to double it because it travels there and back. The speed is the total distance divided by the time.

Answer 5

HAve a friend go stand a known distance away and set off firecrackers at night. The further away the better. Time the interval between the time you see the flash, which arrives virtually instantaneously, and the time you hear the bang.