Question

A source of sound waves approaches a stationary observer through a uniform medium. Compared to the frequency and wavelength of the emitted sound, the observer would detect waves with a? A) Higher frequency and shorter wavelength B) Higher frequency and longer wavelength C) Lower frequency and shorter wavelength D) Lower frequency and longer wavelength

Answer 1

If the distance between the source and the observer is shrinking ...
no matter which one is actually moving ... then the observer hears
higher frequency / higher pitch / shorter wavelength than the sound
that actually left the source. (A)

Answer 2

Answer: The correct option is (A).

Explanation:

Doppler effect is the phenomenon in which there is increase or decrease in the frequency when there is a relative motion between the source and the listener.

Frequency and wavelength has an inverse relationship.

When the source and the listener are approaching towards each other then there is increase in frequency.

When the source and the listener are approaching away from each other then there is decrease in frequency.

In the given problem, A source of sound waves approaches a stationary observer through a uniform medium. The observer would detect higher frequency of the sound wave but having shorter wavelength.

Therefore, the correct answer is "Higher frequency and shorter wavelength".