Question

What constant torque should be applied to a disc of mass 16 kg and diameter
0.5 m so that it acquires an angular velocity of 4 π rad /s in 8 sec? The disc is
initially at rest and rotates about an axis through the centre of the disc and in a
plane perpendicular to the disc. ​

Answer 1

Answer:

Moment of inertia of the disc I=MR²/2

                                                 =16×(0.25)²/2

                                                 =0.5 kg m²

∴Torque τ=Iα

                =0.5×(4/8)

                =0.5×1/2

           ∴τ=0.25 N m