A wire fixed at both ends is 1.0 m long and has a mass of 36g. One of its oscillation frequencies is `250 Hz` and the next higher one is 300 Hz.
(a) Which harmonics do these frequencies represent?
(b) What is the tension in the wire?

Answer

A, B, C, D

Explanation

(a) `f_1/f_2 = 250/300 = 5/6`
So, `f_1` is `5th` harmonic and `f_2` is `6th` harmonic.
(b) `f_1 = (5) = v/(2l) = (2.5 (sqrt(T/mu)))/(l)`
`:. T = (mu f_(1)^(2)l^(2))/(2.5)^2) = ((0.036) (250)^2 (1)^2)/(2.5)^(2)`
=360 N.