A tuning fork w/ frequency of 256 Hz sounded w/ another tuning fork w/ unknown frequency produces 30 beats in 10 seconds. Then, one tine is covered in plasticine and sounded again w/ the unknown frequency tuning fork and produces 20 beats in 10s. What is the frequency of unknown tuning fork.
BF= #beats/total time=f1-f2
= 3 Hz
= 256+/-3 Hz
= 253 or 256 Hz
That's all I got to, I don't know how to use the info from second piece of information to find exact frequency?