Question

If the wavelength of a wave in a medium decreases, it's frequency

• A. remains unchanged.
• B. also decreases.
• C. increases.

Answer 1

The correct option is C increases.

In a medium, the velocity of a sound wave is fixed if the medium's properties are not changed

We know, v = $\lambda$ f

Where, v = wave velocity

$\lambda$ = wavelength

f = wave frequency

So, if v is constant and wavelength is decreased you don't need physics to tell you what will happen to its frequency.

v = $\lambda \downarrow f\uparrow$

The frequency will have to increase to keep the velocity constant.