Question

An accurate and reliable audio oscillator is used to standardize a tuning fork marked as 512 Hz. When the oscillator reading is 514 two beats are heard per second. When the oscillator reading is 510, the beat frequency is 6 Hz. The frequency of the tuning fork is:

• A. 518
• B. 516
• C. 506
• D. 510

Answer 1

Answer: (B)

516

Answer 2

When a tuning fork is marked as 512 Hz, oscillator reading is 514.
The beat are heard, so the frequency of the tuning fork is $514\,\pm \,2\,=516$ or 512. When the oscillator reading is obtained as 510 Hz.
The frequency of tuning fork is $510\,\pm \,6=516$ or 504.
The common value is 516 Hz.
Therefore the frequency of tuning fork is 516 Hz.
So, the correct option is B: 516.