Answer:
(a) 0.426 rad/s
(b) Before 296.225 J and After 148.5 J
Explanation:
At the center of merry-go-round, the person's weight is 75 Kg with moment of inertia of 820 kgm2 and the initial angular velocity is 0.85 rad/s
At the edge, the new angular velocity gained depends on the new moment of inertia
Here, the final moment of inertia is given by Initial moment of inertia + where M is the mass and R is the radius of merry-go-round
Final moment of inertia=
From the law of conservation of angular momentum as torque is zero
and making
the subject then
where and
are initial and final moment of inertia,
and
are initial and final angular velocity.
Substituting the provided values
(b)
Initial rotational kinetic energy is given by
The final rotational kinetic energy is given by