Question

What is the reduction of speed of a rotating body when stroke by a small mass

Answer 1

Explanation:

Initial frequency of rotation ν

i

=1800 rpm =1800/60=30 rps

Thus initial angular frequency w

i

=2πν

i

=60π rad/s

Final frequency of rotation ν

f

=3000 rpm =3000/60=50 rps

Thus final angular frequency w

f

=2πν

f

=100π rad/s

∴ Angular acceleration α=

t

w

f

−w

i

OR α=

20

100π−60π

=2π rad/s

2