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NEET2024PhysicsLaws of MotionActual

A bob is whirled in a horizontal circle by means of a string at an initial speed of 10 rpm. If the tension in the string is quadrupled while keeping the radius constant, the new speed is:

Options

  1. A20 rpm
  2. B40 rpm
  3. C5 rpm
  4. D10 rpm

Correct answer

A. 20 rpm

Step-by-step solution

In horizontal circular motion, T=m ^2 r For constant m and r, T ^2T=4 T (Given) ^ =2 =20 rpm

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