Question

A string of length $10.0m$ and mass $1.25kg$ is stretched with a tension of $50N$. If a transverse pulse is created at one end of the string, the time taken by it to reach the other end is

• A. $0.5s$
• B. $1.0s$
• C. $1.5s$
• D. $2.0s$

Answer 1

Answer: (A)

$0.5s$

time taken$=\frac{l}{v}=\frac{l}{\sqrt{T/\left(m/l\right)}}=\frac{l\sqrt{m}}{\sqrt{Tl}}=\frac{\sqrt{ml}}{\sqrt{T}}$
$\sqrt{\frac{1.25\times 10}{50}}$ $(\because v=\sqrt{\frac{T}{m/l}})$
$=\sqrt{0.25}$
$=0.5seconds$