A string of length L is fixed at one end a

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A string of length $L$ is fixed at one end and carries a mass $M$ at the other end. The string makes $2/\pi$ revolutions per second around the vertical axis through the fixed end as shown in the figure, then tension in the string is

A

$ML$

B

$2 \,ML$

C

$4\, ML$

D

$16 \,ML$

A string of length $L$ is fixed at one end and carries a mass $M$ at the other end. The string makes $2/\pi$ revolutions per second around the vertical axis through the fixed end as shown in the figure, then tension in the string is

$T\sin \theta = M{\omega ^2}R$…(i)

$T\sin \theta = M{\omega ^2}L\sin \theta $…(ii)

From (i) and (ii)

$T = M{\omega ^2}L$

$ = M\,4{\pi ^2}{n^2}L$

$ = M\,4{\pi ^2}{\left( {\frac{2}{\pi }} \right)^2}L$

$ = 16\,ML$