Question

Two tuning forks when sounded together produce 5 beats per second. The frequency of one of them is 250 Hz. When the other fork is slightly loaded, they produce 7 beats/s. Then the frequency of other tuning fork without loading is
A. 243 Hz
B. 255 Hz
C. 245 Hz
D. 257 Hz

Answer 1

Correct Answer - C
`n_(2) = n_(1) +- 5`
`= 250 +- 5 = 255 or 245`
`n_(2) = n_(1) + 7`
`= 250 +- 7 = 257 or 243`
`n_(2)` is loaded it frequency decreases before loading increases by 2 difference of beat frequency
`n_(2) = 245Hz`