11.7

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11.7   Angular Momentum
Figure shows a particle of mass m with linear
momentum as it passes
through point A in an xy plane. The angular
momentum, of this particle with respect to the
origin O is a vector quantity defined as
The direction of the angular momentum vector is
given by the right-hand rule. It is perpendicular
to the plane formed by the position and linear
momentum vectors. SI unit of angular momentum
kg m2/s J.s
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11.8/9   Newtons Second Law
The (vector) sum of all the torques acting on a
particle is equal to the time rate of change of
the angular momentum of that particle.
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11.10   The Angular Momentum of a Rigid Body
Rotating About a Fixed Axis
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11.11   Conservation of Angular Momentum
If the net external torque acting on a system is
zero, the angular momentum of the system remains
constant, no matter what changes take place
within the system.
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11.11   Demonstration on Conservation of Angular
Momentum
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Angular Momentum in Sports
The springboard diver.
Long jump.