Question

A transverse wave of equation $y=2\sin (0.01x+30t)$ moves on a stretched string from one end to another end. In the equation of wave, $x$ and $y$ are in cm and t in second. The time taken by wave to reach from one end to another end of string is $5s$. The length of string is

• A. $10m$
• B. $100m$
• C. $150m$
• D. $160m$

Answer 1

The correct option is C $150m$

$y=2\sin (0.01x+30t)$
$k=0.01$ and $\omega =30$
$v=\frac{\omega }{k}$
$=\frac{30}{0.01}$
$=3000cm/s.$
$=30m/s.$

$length=v\times t$
$=30\times 5$
$=150m$