Question

A string of mass 2.50 kg is under a tension of 200 N. The length of the stretched string is 20.0 transverse jerk is struck at one end of the string. How long does the disturbance take to reach the other?

Answer 1

velocity of wave in stretched string is given by

$V=\sqrt{\frac{T}{m}}$

if $l=lengthofstring$ then line taken by wave ti reach the other end is

$t=\frac{l}{V}=l\sqrt{\frac{m}{T}}$

we have

$l=20m,T=200Nm=massperunitlength=\frac{2.5}{20}=\frac{1}{8}Kg/m\therefore t=20\sqrt{\frac{\frac{3}{8}}{200}}=0.5sec$.