Question

A source emits sound with a frequency of 16246 Hz. Both it and an observer are moving toward each other, each with a speed of 141 m/s. What frequency (in Hz) does the observer hear?

Answer 1

Answer:

39267.96 Hz

Explanation:

Given:

Frequency emitted = 16246 Hz

Speed of source = 141 m/s

Speed of observer = 141 m/s

Let the velocity of sound is v = 340 m/s

Doppler effect is nothing but the change in the wavelength or frequency of a wave relative to the observer, who is also moving relative to the origin of the wave source.

Therefore, Doppler effect when the source and the observer moves towards each other,

Frequency heard = ( frequency emitted ) ( Velocity of sound + Speed of the observer ) / ( velocity of sound - speed of source )

                      16246 x ( 340 + 141 ) / ( 340 - 141 )

                         = 39267.96 Hz