A body is uniformly rotating about an axis fixed in an inertial frame of reference. Let be a unit vector along the axis of rotation and be the unit vector along the resultant force on a particle P of the body away from the axis. The value of is
D. None of these
In case of a rotational motion the force is always a central force. So, θ=π/2.
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The displacement vector of a particle of mass m is given by r (t) = î A cos ωt + ĵ B sin ωt.
(a) Show that the trajectory is an ellipse.
(b) Show that F = −mω2r
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