15 beats are heard in 5 seconds when a piano key and a tuning fork of slightly higher frequency (440 Hz) are struck at the same time. What is the frequency of the sound emitted by the piano key?

Answer 1

440-f=15

Answer 2

Number of beats heard per second = 15/5 = 3 beats/sec. We know number of beats heard per second = difference in frequency of the two sound waves. So 3 = 440 - fp, where fp is the frequency of the piano key which is slightly lower than 440 Hz. Solving for fp, we get fp = 337 Hz.

Answer 3

337

Answer 4

You mean 437 in your final answer. 440-3=437 not 337