As an ice skater begins a spin, his angular velocity is 3.75 rad/s. After pulling in his arms, his angular speed increases to 6.45 rad/s. Find the ratio of the skaters final moment of inertia to his initial moment of inertia.

Respuesta :

Answer:

The ratio of the skaters final moment of inertia to his initial moment of inertia is 0.338

Explanation:

Moment of inertia = mr^2 = m(v/w)^2 = mv^2/w^2

Initial angular velocity (w) = 3.75 rad/s

Initial moment of inertia = mv^2/3.75^2 = 0.071mv^2

Final angular velocity (w) = 6.45 rad/s

Final moment of inertia = mv^2/6.45^2 = 0.024

Ratio = 0.024/0.071 = 0.338

Answer:

1 : 1.72.

Explanation:

Moment of inertia {\displaystyle I}I is defined as the ratio of the net angular momentum, L of a system to its angular velocity,w around a principal axis.

I = L/w

Given:

w1 = 3.75 rad/s

w2 = 6.45 rad/s

Therefore,

I1 = L1/3.75

= 0.27L1

I2 = L1/6.45

= 0.155L1

At constant momentum, L ratio of the initial moment of inertia to the final moment of inertia =

3.75 I1 : 6.45 I2

= 1 : 1.72.

1.74