A sound source of frequency 1 000 Hz moves at 50.0 m/s toward a listener who is at rest.What is the apparent frequency heard by the listener? (speed of sound = 340 m/s)
A)853 Hz
B)872 Hz
C)1 150 Hz
D)1 170 Hz

Question

Quizplus · Accepted Answer

The formula for calculating the apparent frequency is given by:
f' = f ((v+/-vd) / v)
where,
f = actual frequency of the source
v = speed of sound
v = speed of the source
d = distance between the source and the listener

In this case, we have:
f = 1 000 Hz
v = 340 m/s
v = 50.0 m/s
d = not given, so we assume it as 1 meter (since it doesn't affect the answer to a significant extent)

Substituting the values in the formula, we get:
f' = 1 000 ((340+/-50) / 340)
For the source moving towards the listener:
f' = 1 170 Hz

Therefore, the answer is D, 1 170 Hz.

A Sound Source of Frequency 1 000 Hz Moves at 50.0