Q.

If the initial tension on a stretched string is doubled, then the ratio of the initial and final speeds of a transverse wave along the string is               [2022]
 

1 1 : 1  
2 2:1  
3 1:2  
4 1 : 2  

Ans.

(3)

Velocity of a transverse wave in a stretched string is given by

v=Tμ                                                      ...(i)

Where T is the tension in the string and μ is the mass per unit length of the string.

If tension T is doubled, then final speed of the wave in the string will be,

v'=2Tμ                                              ...(ii)

From eq. (i) and (ii)

vv'=12