Question

When two tuning forks A and B are sounded together, x beats/sec are heard. Frequency of A is n. Now when one prong of fork B is loaded with a little wax, the number of beats/sec decreases. The frequency of fork B is –

• A. n + x
• B. n – x
• C. n – x²
• D. n – 2x

Answer 1

Answer: (A)

n + x

Answer 2

As 'n' is beat frequency

n – n_B = x ……(1)

or

n_B – n = x ……(2)

On loading the wax on 'B' frequency of fork 'B' decreases, So 2^nd relation is correct.

n_B = n + x