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    Rotation

    A rotation is a curler movement of an object around a center of rotation. A 3-D object rotates around an imaginary line called a rotation axis. It this axis is within the body and passes through its center of mass the body will rotate upon itself or spin. A rotation about an external point is called a revolution when it is produced by gravity.

    A rotation is a rigid body movement which is unlike a translation which keeps a point fixed. All rigid body movements are rotations, translation or combination of the two. A rotation is a progressive radial orientation to a common point. The distinction between a rotation and an orbit is the location of the axis of the rotation.

    Rotations around the x, y, and z axes are called principal rotations. Rotations around any axis can be performed by taking a rotation around the x axis, followed by a rotation around the y axis, followed by the rotation around the z axis.

    The speed of rotation is given by angular frequency. The time-rate of change of angular frequency is angular acceleration. Said change is caused by torque. According to the right-hand rule, the direction away from the observer is associated with clockwise rotation and the direct towards the observer with counter-clockwise rotation.

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    A Horizontal Seismometer with a Pendulum

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    Minimum Value of Height Change

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    Student's Angular Velocity

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    Inertia and Weighing Stop Signs

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    A 15--diameter CD has a mass of 24 .

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    Rotational Motion of a Wheel

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    Magnitudes and Angular Positions of Masses

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    Physics: Centrifugal force for glass and board swung on strings

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    Dynamics; Three problems

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    Kinetic Energy and Merry Go Round

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    Mass and Average Density of Mars

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