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The stretch of a spring and the force that caused it
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· The force applied to an ideal spring will be proportional to its stretch. |
· The graph of force on the y axis versus stretch on the x axis will yield a slope of k, the spring constant (弹性系数) . |
Work done by spring force:  |
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Motion on a curved path—Example 6.8 |
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Under constant force:
The work is independent of the actual path taken by the particle.
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Watt about power? |
Power is the time rate at which the work is done.
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Average power:  unit: watt (W)
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Instantaneous power:  |
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