Qn on Rotational Kinetic Energy

[lavieenrose]

Homework Statement

Crab Nebula releases energy at a rate of 5x10³¹ W, obtaining its energy from the rotational kinetic energy K of a neutron star at its centre.
Period of neutron star's rotation = 0.0331s. T increases by 4.22 x 10-¹³s per second.

What is the moment of inertia of the neutron star?

Homework Equations

dK/dt = -(4$$\pi$$²I/T³) (dT/dt)
This was the first part of the question which I managed to prove already.
*Note: the pi is not supposed to be in superscript.

The Attempt at a Solution

I equated the power of the star to the above differential equation. Solving for I should be quite easy, but somehow my answer (1.1x 10³⁸) is different from the answer provided (1.1 x 10³⁰).

 

[ehild]

Your result looks correct.

ehild