Question

A wire having a linear mass density `5.0xx10^(3) kg//m` is stretched between two rigid supports with tension of 450 N. The wire resonates at a frequency of `420 Hz`. The next higher frequency at which the same wire resonates is` 480 N`. The length of the wire is
A. `2.0m`
B. `2.1m`
C. `2.5m`
D. `3m`

Answer 1

Correct Answer - C
Two consecutive frequencies are `420Hz & 480Hz.`
So the fundamental frequency will be `60Hz`.
`:. 60=(1)/(2xxl)sqrt((450)/(5xx10^(-3)))`
`rArr l=2.1m`