Answer to Question #163240 in Physics for Earl

Question

A trumpet emits a sound frequency equivalent to 100Hz. If the person using the trumpet is moving towards the listener, what would be the perceived frequency of the listener if the velocity of the sound is 350 m/s and the man using the trumpet is moving at the rate of 5m/s?

Answer 1

We can find the frequency heard by the listener from the Doppler Shift formula:

$$f_o=f_s(\dfrac{v}{v-v_s}),$$ $$f_o=100\ Hz\cdot(\dfrac{350\ \dfrac{m}{s}}{350\ \dfrac{m}{s}-5\ \dfrac{m}{s}})=101.45\ Hz.$$