A person carrying a whistle emitting continuously a note of `272 Hz` is runnig towards a
Channel: Doubtnut
Date: 2020-01-19

A person carrying a whistle emitting continuously a note of `272 Hz` is runnig towards a reflecting surface with a speed of `18km//h`. The speed of sound in air is `345ms^(-1)` The number of beats heard by him is