Question

A motorcyclist is traveling north on a road at a speed of 23.0 m/s. A police car, traveling south at a speed of 40.0 m/s, approaches with its siren producing sound at a frequency of 2500 Hz. (Enter your answers in Hz. Assume that the speed of sound in air is 343 m/s.) (a) What frequency does the motorcyclist observe as the police car approaches

Answer 1

f ’= 3019.8 Hz

Step-by-step explanation:

This is an exercise of the Doppler effect, that is, of the relative movement of the source (s) and the observer (o)

`f' = f_o (v +v_o)/(v -v_s)`

in the case of the source and the observer approaching, if they move away the signs are exchanged

let's calculate

f ’= 2500
`(343 + 23)/(343 - 40)`

f ’= 2500
`(366)/(303)`

f ’= 3019.8 Hz