question_answer

A stretched string of length\[l,\]fixed at both ends can sustain stationary waves of wavelength  given by

A)  \[\lambda =\frac{{{n}^{2}}}{2l}\]

B)  \[\lambda =\frac{{{I}^{2}}}{2n}\]

C)  \[\lambda =\frac{2l}{n}\]

D)  \[\lambda =2\ln \]

Correct Answer: C

Solution :

 \[\lambda =\frac{2l}{n},\]where \[n=\]number of loops. at \[n=1\] \[\lambda =2l\] at \[n=2\] \[\lambda =\frac{2l}{2}\] at \[n=3\] \[\lambda =\frac{2l}{3}\] at \[n=n\] \[\lambda =\frac{2l}{n}\]