Question

Standing waves are produced in a 10 m long stretched string. If the string

vibrates in 5 segments and the wave velocity is 20 m/s, the frequency is

[CBSE PMT 1997; AIIMS 1998; JIPMER 2000]

• A. 2 Hz
• B. 4 Hz
• C. 5 Hz
• D. 10 Hz

Answer 1

The correct option is C

5 Hz

String vibrates in five segment so $\frac{5}{2}\lambda =l\Rightarrow \lambda =\frac{2l}{5}$

Hence n = $\frac{v}{\lambda }=5\times \frac{v}{2l}=5\times \frac{20}{2\times 10}=5Hz.$