Answer:
Explanation:
Initially the two boys were sitting on the periphery , total moment of inertia
= 1/2 M r² + 2mr² ; M is mass of the merry go round , m is mass of each boy and r is the radius
1/2 x 200 x 2² + 2 x 40 x 2²
= 400 + 320
I₁ = 720 kg m²
Finally the two boys were sitting at the middle , total moment of inertia
= 1/2 M r² + 2m( r/2)² ; M is mass of the merry go round , m is mass of each boy and r is the radius
1/2 x 200 x 2² + 2 x 40 x 1²
= 400 + 80
I₂ = 480
Now the system will obey law of coservation of angular momentum because no torque is acting on the system.
I₁ω₁ = I₂ω₂ , I₁ and ω₁ are moment of inertia and angular velocity of first case and I₂ and ω₂ are of second case.
720 X 12 = 480 ω₂
ω₂ = 18 rad / s
Answer:
Only at point a
Explanation:
If the velocity is greater than zero, than the object must be moving.