Came across this forum while searching the net for help. It's great to have a forum dedicated to physics.(adsbygoogle = window.adsbygoogle || []).push({});

So hi to everyone :)

Now to business.

I'm stuck with this question.

If you weigh 660N on the earth, what would you weigh on the surface of a neutron star that has the same mass as our sun and a diameter of 22.0km ?

Take the mass of the sun to be m_s = 1.99×10^30kg, the gravitational constant to be G = 6.67×10^-11 N m^2/kg^2, and the acceleration due to gravity at the earth's surface to be g = 9.810 m/s^2.

My working out:

*r_n = radius of neutron

*m_n = mass of neutron

*m_me = mass of me

r_n = 11000m

m_n = 1.99 x 10^30kg

m_me = w/g = 660/9.810 = 67.27828746kg

= (G * m_n * m_me) / r_n^2

= (6.67x10^-11 * 1.99x10^30 * 67.27828746) / 11000^2

= 7.380205N

----

Now I'm told that the answer is wrong.

So can someone tell me where I went wrong ?

Thanks in advance.

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# Homework Help: Weight on a Neutron Star ?

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