# Effects of force out of mass center

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KaRei    119
Hello,
it has been some time already since I had physics on school or university and so I'd welcome a help with solving this situation:

Have an object with a center of mass T
A gravitational force Fg is constant in whole the object, so its point of action is in T
Point P on the surface of the object is a point of action of outer force F

I am thinking now about the translation and rotation effects these forces will have on the object? What direction will have the final translation force and where would be the center of rotation?
I tried to combine the forces somehow, but everything I tried looks like an absolute nonsense.

[img]http://img580.imageshack.us/img580/2712/forceonobject.png[/img]

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szecs    2990
Well, the force will be vertical in that case, you just have to sum the two vectors. The other thing that comes into play is the [b]torque[/b]. Look into that and "rigid body physics", "rigid body dynamics" too.

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KaRei    119
[quote name='szecs' timestamp='1305698517' post='4812271']
Well, the force will be vertical in that case, you just have to sum the two vectors. The other thing that comes into play is the [b]torque[/b]. Look into that and "rigid body physics", "rigid body dynamics" too.
[/quote]

Thanks. The simple sum of the forces for translation came on my mind but I thought the position of F origin would couse some horizontal translation too. That made me puzzled.
Thanks again for quick response

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szecs    2990
Don't confuse forces with real objects. I mean if an object comes form the bottom in the direction you have drawn, then the circle WOULD BE translated horizontally. But that's different, because in that case, the force WOULD NOT BE vertical. I hope you understand what I mean. You can't always "convert" real life scenarios that easily. And forces are not always intuitive to find.