Question

$y=15\sin (660t–0.02x)$can be used to calculate the equation of a progressive wave. The wave has a frequency of

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

Answer 1

The correct option is A

$330Hz$

Step 1. Given data:

$y=15\sin (660\mathrm{\pi t}-0.02\mathrm{\pi x})$

Step 2. Formula used:

The general equation for a progressive wave is,

$y(x,t)=A\sin (\omega t-kx)$

Step 3. Calculating the frequency,

On comparing the given equation and the general equation of progressive wave we get,

Hence, $\omega =660\pi$ ($\omega =$Angular frequency, $f=$Linear frequency)

$\begin{array}{rcl}& \Rightarrow & 2\pi f=660\pi \\ & \Rightarrow & f=\frac{660\pi }{2\pi }\\ & =& 330\end{array}$

$f=330Hz$

Thus, the frequency is$330Hz$

Hence, option A is the correct answer.