Q. A source emits a sound of frequency of 400 Hz, but the listener hearts its 390 Hz. Then
A) The listener is moving towards the source
B) The source is moving towards the listener
C) The listener is moving away from the source
D) The listener has a defective ear
Explanation
(c) Real frequency v=400 Hz
Apparent frequency v’=390Hz
V’<v
So, the distance between the source and listener increases or the listener is going away from source.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.