Question

In the wave equation
$y=0.5\sin \frac{2\pi }{\lambda }(400t-x)m$
the velocity of the wave will be :

• A. $200m/s$
• B. $200\sqrt{2}m/s$
• C. $400m/s$
• D. $400\sqrt{2}m/s$

Answer 1

Answer: (C)

$y=0.5\sin \left(\frac{2\pi }{\lambda }400t-\frac{2\pi }{\lambda }x\right)$
$\omega =\frac{2\pi }{\lambda }400$
$K=\frac{2\pi }{\lambda }$
$v=\frac{\omega }{k}[v=400m/s]$