Question

Length of a sonometer wire is either 95 cm or 100 cm. In both the cases a tuning fork produces 4 beats then the frequency of tuning fork is :-
A. 152
B. 156
C. 160
D. 164

Answer 1

Correct Answer - B
For sonometer wire
`nxx100=(n+1)xx95`
n=no of harmonics
`rArr n =19`
`:. f=19((L)/(2))+4=20((L)/(2))-4rArr L=16`
`rArrf=20((L)/(2))-4=156 Hz`