# Net gravitational force

Confused :(

## Homework Statement

A 200 kg object and a 500 kg object are separated by 0.500 m. Find the net gravitational force exerted by these objects on a 50.0 kg object placed midway between them.

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DaveC426913
Gold Member
We don't spoonfeed homework here. Show your attempts.

I have:
F= Gm1m2/r^2
F= G(50.0kg)(500kg-200kg)/0.25m^2 =240000N toward 500kg

I feel that I have it setup right but for some reason when I calculate I get 2400000 which seems wrong to me.

DaveC426913
Gold Member
I have:
F= Gm1m2/r^2
F= G(50.0kg)(500kg-200kg)/0.25m^2 =240000N toward 500kg

I feel that I have it setup right but for some reason when I calculate I get 2400000 which seems wrong to me.
What value have you used for G?

What value have you used for G?

9.8 m/s^2

DaveC426913
Gold Member
9.8 m/s^2
That's little g. You want http://en.wikipedia.org/wiki/Gravitational_constant" [Broken].

Last edited by a moderator:
Any advice on how I find it?

Any advice on how I find it?

The easiest way, I would think, would be to click on the link DaveC provided under 'big G'. The easiest way, I would think, would be to click on the link DaveC provided under 'big G'. If it was a snake it would have bitten me.

So G is 6.674 x 10^-11N (m/kg)^2 correct?

That would mean my equation is:
F= 6.674 x 10^-11(50.0kg)(500kg-200kg)/0.25m^2 =1.60176 x 10^-5N toward 500kg?

Last edited:
Redbelly98
Staff Emeritus