A band playing music at a frequency is moving towards a wall at a speed

PHYSICS · Subjective · AP · Physics 2: Algebra-based · Waves Sound and Physical Optics · Waves Sound and Physical Optics

Problem

A band playing music at a frequency

f

is moving towards a wall at a speed

v_b

. A motorist is following the band with a speed

v_m

. If

v

is the speed of sound, obtain an expression for the beat frequency heard by the motorist.