A star of mass equal to two solar masses and radius 106 km rotates about its axis with an angular speed of 10-6 rads-1. What is the angular speed of the star, when it collapses (due to inward gravitational forces) to a radius of 104 km?

7 views

1 Answers

Here, R1 = 106 Km

ω1 = 10-6 rads-1, ω2 = ? R2 = 104 Km

As I1ω1 = I2ω2

\(\therefore\) ω = \(\frac{I_1\omega_1}{I_2}=\cfrac{\frac25MR_1^2\omega_1}{\frac25MR_2^2}\)

\(=(\frac{R_1}{R_2})^2\)ω1

ω2 = \(\left(\frac{10^6}{10^4}\right)\)x 10-6 = 10-2 rad/s

7 views

Related Questions