If we somehow apply a force direct to the center of gravity (existing inside an object ) , does it increase the angular velocity of a rotating object as it does in normal case ?
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what is a normal case? – Peter R May 26 '16 at 17:38
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no, it does not change it – May 26 '16 at 17:47
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See if this (and links therein) help you. http://physics.stackexchange.com/a/81078/392 – John Alexiou May 28 '16 at 19:40
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If the center of mass is the same as the center of gravity then it does not change the angular velocity. As far as we know the inertial mass is the same as gravitational mass and hence the center of mass is always also a center of gravity (defined as a center of gravitational mass).
Some people define a center of gravity as point where the average external force of gravity is attached. Then if the external gravitational field is not uniform the center of mass and this average center of gravity may be in different positions. This means that the object will change the angular velocity.
Veritas
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If what you mean is Center of Mass, then, no, it will not change the angular velocity (if there are no other external torque acting on the object, and the object is not attached in any way to other objects, i.e, glued, or attached to a fixed rotating rod or another object, who's rotating axis does not intersect the Center of Mass of the object attached). In order to change the angular velocity, you need to apply Torque, $T = Frsin\theta$, where $r$ is measured from the center of mass to the point where you applied the force.
philip_0008
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