Question

A copper rod at 25°C is 2.5 m long. How long would it take a sound to move through the rod from one end to another? how would I do this?

Answer 1

Length of the copper rod = 2.5 meters
Speed at which sound travels through copper = 3560 meter per second
Let us assume the time taken
by sound to cover the given distance = x seconds
We already know that 
Speed = Distance/ Time
Then
Time = Distance/ Speed
x = 2.5/3560 seconds
   = 0.0007 seconds.
This can ve done by hitting one end of the rod and then receiving the sound at the other end and using the stop clock to measure the time taken.

Answer 2

Answer;The time taken by they sound to move from one end of the rod to another end is 0.00054 seconds.

Explanation;

Speed of sound in the copper = 4600 m/s

Length of the copper  rod = 2.5 m

$Speed=\frac{Distance}{\text{Time taken}}$

Distance covered by the sound = length of the copper

$4600 m/s=\frac{2.5 m}{T}$

$T=\frac{2.5 m}{4600 m/s}=0.00054 s$

The time taken by they sound to move from one end of the rod to another end is 0.00054 seconds.