Question

A hollow cylinder of mass 10 kg rotates about its
own axis with angular speed 50 rad.s-1. If the radius
of cylinder is 40 cm, then the magnitude of the an-
gular momentum of the cylinder about its axis is
(1) 20 JS
(2) 40 JS
(3) 80 JS
(4) 60 JS​

Answer 1

Answer:

option 4

Explanation:

The moment of inertia of a solid cylinder=mr

2

/2

=

2

1

×20×(0.25)

2

=0.625kgm

2

Therefore kinetic energy=

2

1

Iω

2

=3125J

Angular momentum ,L=Iω

=0.625×100

=62.5Js