Introduction: The laws which govern rotational motion follow from Newton’s laws just as do those which govern linear motion. If an object is rotating about a fixed axis, then Newton’s law describing its rotational motion can be expressed as, ?= ??
Where ?is the net moment of force, or torque, about the axis which results in an angular acceleration, ?
2.The moment of inertia of an extended rigid body, on the other hand, depends on the way in which its mass is distributed relative to the axis of rotation. Such a body can be thought of as made up ofa very large number of elemental masses and the total moment of inertia is then the sum of contributions from all such masses. If mi represents the mass of one such element located at a distance of rifrom the axis, then the total moment inertia can be written as,?