Question

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

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

Answer 1

Answer: (C)

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