Question

Two sound sources generate pure tones of 65 Hz and 75 Hz. What is the beat frequency?

a
15Hz
b
20Hz
c
10Hz
d
5Hz

Answer 1

• D) 5 Hz

Step-by-step explanation:

First, prime factorize the two pure tone values.

• 65 = 5 x 13
• 75 = 5 x 5 x 3

It is clear that the Highest Common Factor (HCF) is 5

The two tones can only be pure if they resonate from the same beat frequency.

As 5 is a common factor, it is the beat frequency.