Question

A wave of frequency $500Hz$ travels with a speed of $360m{s}^{-1}$. The distance between two nearest points which are ${60}^{\circ }$ out of phase is

• A. $12cm$
• B. $18cm$
• C. $50cm$
• D. $24cm$
• E. $6cm$

Answer 1

Answer: (A)

$12cm$

Given, $v=360m{s}^{-1},\lambda =500Hz$
We know that, $v=f\lambda ,\lambda =\frac{v}{f}$
Wavelength, $\lambda =\frac{360}{500}=0.72=72cm$
The distance between two nearest points which are ${60}^{\circ }$ out of phase
$=\frac{\lambda }{6}=\frac{72}{6}=12cm$.