MCQ
A sphere of mass $m$ is tied to end of a string of length $l$ and rotated through the other end along a horizontal circular path with speed $v$. The work done in full horizontal circle is
  • $0$
  • B
    $\left( {\frac{{m{v^2}}}{l}} \right)\,.\,2\pi l$
  • C
    $mg\,.\,2\pi l$
  • D
    $\left( {\frac{{m{v^2}}}{l}} \right)\,.\,(l)$

Answer

Correct option: A.
$0$
a
(a)Work done by centripetal force in uniform circular motion is always equal to zero.

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