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Qn on Rotational Kinetic Energy

  • #1

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[tex]\pi[/tex]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).
 

Answers and Replies

  • #2
ehild
Homework Helper
15,478
1,854
Your result looks correct.

ehild
 

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