A wave is traveling in a string at 60 m/s.When the tension is then increased 20%,what will be the resulting wave speed?
A)also 60 m/s
B)66 m/s
C)72 m/s
D)55 m/s

Question

Quizplus · Accepted Answer

The wave speed in a string is given by the equation v = sqrt(T/μ), where T is the tension in the string and μ is the mass per unit length. 
If the tension is increased by 20%, then the new tension becomes T' = T + 0.2T = 1.2T. 
Therefore, the new wave speed becomes v' = sqrt((1.2T)/μ) = sqrt(1.2)*sqrt(T/μ) = 1.095*60 m/s = 65.7 m/s, which is closest to option B) 66 m/s.

A Wave Is Traveling in a String at 60 M/s