Figure shows a person standing somewhere in between two identical tunning forks, each vibrating at `512 Hz. If both the tuning forks move towards right at a speed of `5.5 ms^-1`, find the number of beats heard by the listener. Speed of sound in air `=330 ms^-1`.

Answer

A, B, D

Explanation

According to the data
`V_s=5.5 m/s` of each tuning fork
So, the apparent frequency heard from the tuning fork on the left
`=f^1=(330/(330-5.5))xx512`
`=520.68Hz`
Similarly, apparent frequency from the tunign fork on the righ `f^11(330/(330-5.5))xx512`
`=503.60Hz`
so, beats produced
`=520.68-503.60=17.5Hz`