Question

A copper rod at 25°C is 1.5 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

Speed of sound in copper at normal temperature ( 293.15 K ) is:
v = 3,570 m / s
L = 1.5 m
t = L / v = 1.5 m / 3,570 m/s
t = 0.00042 s = 4.2 * 10^(-4) s 

Answer 2

Answer : Time, t = 0.00042 s

Explanation :

It is given that,

Length of the copper rod, $l=1.5\ m$

The speed of sound in copper wire at $25^0\ C$ is, $v=3560\ m/s$

We know that the speed of the sound wave is given by :

$s=\dfrac{d}{t}$

Distance travelled is equal to the length of the wire.

$t=\dfrac{d}{s}$

$t=\dfrac{1.5\ m}{3560\ m/s}$

$t=0.00042\ s$

Hence, this is the required solution.