Question

A string is stretched betweeb fixed points separated by `75.0 cm`. It observed to have resonant frequencies of `420 Hz` and `315 Hz`. There are no other resonant frequencies between these two. The lowest resonant frequency for this strings is
A. `10.5 Hz`
B. `105 Hz`
C. `1.05 Hz`
D. `1050 Hz`

Answer 1

Correct Answer - 2
`(n + 1) (v)/(2l) = 420 …..(1)`
`(nv)/(2l) = 315 ….(2)`
`(1) - (2) (V)/(mu) = 105 Hz , f_(min) = = 105 Hz`