A uniform solid disk of radius and mass spins counter-clockwise at about its central axis

PHYSICS · Single correct · A Level · Physics · Engineering physics · Engineering physics

Problem

A uniform solid disk of radius

0.20\,\text{m}

and mass

2.0\,\text{kg}

spins counter-clockwise at

10\,\text{rad}\,/\text{s}

about its central axis. A constant braking torque of

0.40\,\text{N}\cdot\text{m}

acts clockwise on the disk for

5.0\,\text{s}

. What is the disk’s angular speed immediately after the torque is removed? (a)

15\,\text{rad}\,/\text{s}

clockwise (b)

40\,\text{rad}\,/\text{s}

clockwise (c)

50\,\text{rad}\,/\text{s}

clockwise (d)

40\,\text{rad}\,/\text{s}

counter-clockwise