A tuning fork A, marked 512 Hz, produces 5 beats per second, when sounded with another unmarked tuning fork B. If B is loaded with wax the number of beats is again 5 per second. What is the frequency of the tuning fork B when not loaded?
Hint: The frequency of fork B decreases when it is loaded with wax.
Step 1: Find the probable frequencies of fork B.
Frequency of tuning fork A = 512 Hz
Probable frequency of tuning fork B = 517 Hz or 507 Hz
Step 2: Find the actual frequency of fork B.
When B is loaded, its frequency reduces.
If it is 517 Hz, it might be reduced to 507 Hz, giving again a beat of 5 Hz.
If it is 507 Hz, the reduction will always increase the beat frequency, Hence, = 517 Hz
Note: For the production of beats frequencies of the two tuning forks must be nearly equal i.e, slight difference in frequencies