Question

A car speeds past you sounding its horn at a frequency of 1000Hz. The frequency you hear:

Answer 1

f' =1064.1025 Hz

Step-by-step explanation:

We know that from doppler's effect

`f'=(v+v_0)/(v-v_s)f`

f'= observed frequency

f= actual frequency =1000 Hz

v= velocity of sound waves = 332 m/s

v_o= velocity of observer =0

v_s= velocity of source. ( let velocity of car be 20 m/s)

therefore,

`f'=(332+0)/(332-20)*1000`

f' =1064.1025 Hz