Question:

20.A pulley of radius 2m is rotated about its axis by a force `F= (20 t- 5t^2)` newton (where t is measured in seconds) applied tangentially. If the moment of inertia of the pulley about its axis of rotation is `10kg m^2` the number of rotaitons made by the pulley before its direction of motion is reversed, is:

Options :

  • a) Less than 3
  • b) More than 3 but less than 6
  • c) More than 6 but less than 9
  • d) More than 9

Answer :

b) More than 3 but less than 6

Answer Steps :

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