Question

A friend of yours is loudly singing a single note at 412 Hz while racing toward you at 25.8 m/s on a day when the speed of sound is 347 m/s . What frequency do you hear?

Answer 1

5541Hz

Step-by-step explanation:

If the frequency of a wave is directly proportional to the velocity we have;

F = kV where;

F is the frequency

K is the constant of proportionality

V is the velocity

Since f = kV

K = f/v

K = F1/V1 = F2/V2

Given f1 = 412Hz v1 = 25.8m/s f2 = ? V2 = 347m/s

Substituting in the formula we have;

412/25.8=f2/347

Cross multiplying

25.8f2 = 412×347

F2 = 412×347/25.8

F2 = 5541Hz

The frequency heard will be 5541Hz