Question

A long rope is wound around a pulley up to a radius R. Holding the tip of the rope a boy runs away from the pulley with a constant speed maintaining the unwound portion of the rope horizontal. In 4 minutes, the radius R of the wound portion becomes R/ root 2.In what further time R will it become ? ​

Answer 1

Answer:

25rad/s

2

Torque about centre line of cylinder

=F×R

=(30×0.4)Nm

Angular acceleration =

3×(0.4)

2

30×0.4

=

4

100

rad/s

2

=25rad/s

2