Under constant tension and constant mass per unit length, the note produced by a plucked string is 500Hz when the length of the string is 0.90m. At what length is the frequency 150Hz?
A
3m
B
4m
C
5m
D
6m
Verified Correct Answer: A.
Physical Principles & Numerical Solution
F = \(\frac{1}{2L}\)\(\sqrt\frac{T}{m}\)
F1L1 = F2L2
500 x 0.9 = 150 x L2
therefore, L2 = 3m
Source: Myschool Past Questions Archive (Record #27700)