Question

How many vibrations will a tuning fork of frequency 280 hz complete during the sound travels forward in aur by 20m?

Answer 1

may be it will help you

Answer 2

Speed of sound=340m/s
Distance=20m
Speed =distance/time
time=distance/speed
time=20/340
=0.05sec
Frequency=280Hz
Frequency= No.of Vibrations in one second=280Hz
Therefore number of Vibrations completed in 0.05sec
=280x0.05=14 Vibrations