Energy
The mechanical work done by an external agent on a system is equal to the change in kinetic energy of the system:
- General work-energy theorem (translation and rotation)
The work done W by an external agent which exerts a force F (at r) and torque τ on an object along a curved path C is:
where θ is the angle of rotation about an axis defined by a unit vector n.
- Kinetic energy
- Elastic potential energy
For a stretched spring fixed at one end obeying Hooke's law:
where r2 and r1 are collinear coordinates of the free end of the spring, in the direction of the extension/compression, and k is the spring constant.
Read more about this topic: Linear-rotational Analogs
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—Rebecca West (1892–1983)
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—Ralph Waldo Emerson (1803–1882)
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—Helen Hayes (1900–1993)