Rotational Motion

1

A particle performing uniform circular motion has angular momentum L. If its angular frequency is doubled and its kinetic energy halved, then the new angular momentum is

  1. L/4
  2. 4L
  3. L/2
  4. 2L
2

Moment of inertia of a circular wire of mass M and radius R about its diameter is

  1. (MR2)/2
  2. MR2
  3. (MR2)/4
  4. 2MR2
3

A thin uniform rod of length l and mass m is swinging freely about a horizontal axis passing through its end. Its maximum angular speed is ω. Its centre of mass rises to a maximum height of

  1. ωl/(6g)
  2. ω2l2/(2g)
  3. ω2l2/(6g)
  4. ω2l2/(3g)
4

A mass ‘m’ is supported by a massless string wound around a uniform hollow cylinder of mass m and radius R. If the string does not slip on the cylinder, with what acceleration will the mass fall on release?

  1. g
  2. 5g/6
  3. g/2
  4. 2g/3
5

A uniform solid cylindrical roller of mass m is being pulled on a horizontal surface with force F parallel to the surface and applied at its centre. If the acceleration of the cylinder is a and it is rolling without slipping then the value of F is:

  1. ma
  2. 2 ma
  3. 3/2 ma
  4. 5/3 ma