Spherical star spinning at angular velocity omega suddenly collapses to half of its original radius without any loss of mass. Assume the star has uniform density before and after the collapse. What will the angular velocity of the star be after the collapse

The angular velocity of the star after the collapse will be four times greater than its initial angular velocity.

Explanation:

Given:

The initial angular velocity of a spherical star is .

The final radius of the star is half of its initial radius.

The conservation of the angular momentum is given by

where is the moment of inertial of the star.

Consider that the initial moment of inertia of the star is , the final moment of inertia is and the final angular velocity is .

The moment of inertia of a sphere is given by

where is the mass of the sphere and is the radius of the sphere.

The expression for the conservation of angular momentum for the star is given by

Thus, the angular velocity of the star after the collapse will be four times greater than its initial angular velocity.

i think it’s a. this is because if they measured the mass of something with a mass of 150g, then their final answer would have to be approximately 150g. though all of their answers are almost 150, rosa and tran have the closest answers (or the exact answer) to the accurate one.

waves moving from a fast medium to a slow medium will experience a reflection as light travels more slowly than red light. total internal reflection occurs when the critical angle is.