A moving police car plays a sound with constant frequency fo. The police
car moves from the stationary observer on the left, L, towards the
stationary observer on the right, R.
How does the frequency, fL, observed by the observer on the left
compare to the frequency, fR, observed on the right?

Choose 1 answer:
A. fL > fR
B. fL < fR
C. fL = fR