Gravitational Near Earth Surface.

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Homework Statement

Certain neutron stars (extremely dense stars) are believed to be rotating at about 1000 rev/s. If such a star has a radius of 7 km, what must be its minimum mass so that material on its surface remains in place during the rapid rotation?

Homework Equations

The Attempt at a Solution

(7x10^3)(1000*2pi)/6.67*10^-11= 2.0301495

I'm getting it wrong. Any hints why?

 

[ehild]

You forgot to cube the value of R.

ehild