Question

The equation of a progressive wave can be given by $y=15$ $\sin (660\pi t-0.02\pi x)\,cm.$ The frequency of the wave is

• A. 330 Hz
• B. 342 Hz
• C. 365 Hz
• D. 660 Hz

Answer 1

Answer: (A)

330 Hz

Answer 2

Given that $y=15\, \sin (660 \pi t-0.02 \pi x)$
Comparing with general equation of progressive wave, we get
$y=(x, t)=A \sin \left(\frac{2 \pi}{T} t-\frac{2 \pi}{\lambda} x\right)$
$\therefore \frac{2 \pi}{T}=660 \pi$
or $\frac{1}{T}=330$ or $v =330\, Hz$