Answer:
The moment of inertia decreased by a factor of 4
Explanation:
Given;
initial angular velocity of the ice skater, ω₁ = 2.5 rev/s
final angular velocity of the ice skater, ω₂ = 10.0 rev/s
During this process we assume that angular momentum is conserved;
I₁ω₁ = I₂ω₂
Where;
I₁ is the initial moment of inertia
I₂ is the final moment of inertia

Therefore, the moment of inertia decreased by a factor of 4
Newton's Second law of motion:
Force = (mass) x (acceleration)
Force = (15kg) x (8m/s²) = 120 kg-m/s² = 120 newtons
Answer:
3.71 m/s
Explanation:
From the law of conservation of linear momentum, since we are neglecting minor energy losses due to friction then we can express it as
since all the potential energy is transformed to kinetic energy
Making v the subject of the formula then
and here m is the mass of the block, g is acceleration due to gravity, h is the height. Substituting 0.7 m for h and 9.81 for g then we obtain that