If the tension in a stretched string fixed at both ends is changed by `21%` , the fundamental frequency is found to increase by `15 Hz`, then theA. original frequency is 150 HzB. velocity of propagation of the transverse wave along the string increases by 5%.C. velocity of propagation of the transverse wave along the string increases by 10% .D. fundamental wavelength on the string does not change.

If the tension in a stretched string fixed at both ends is changed by

1.	If the tension in a stretched string fixed at both ends is changed by `21%` , the fundamental frequency is found to increase by `15 Hz`, then theA. original frequency is 150 HzB. velocity of propagation of the transverse wave along the string increases by 5%.C. velocity of propagation of the transverse wave along the string increases by 10% .D. fundamental wavelength on the string does not change.
Answer» Correct Answer - A::C::D `f prop sqrt T` `:. f_2/f_1 = sqrt (T_2/T_1)` `:. (f_1+15)/f_1 = sqrt(1.21T_1)/T_1` = 1.1 Solving we get `f_1 = 150 Hz` `v prop sqrtT` `:. v_2/v_1 = sqrt (T_2/T_1)` or ` v_2 = sqrt((1.21 T_1)/(T_1)) v_1 ` ` = 1.1 v_1` Hence, increase in v is 10% `lambda/2 =l ` `:. lambda = 2l ` `:. Fundamental wavelength = 2 lambda is unchanged. `

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