Changing the Direction of Work

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Lifting a mass creates positive work as energy is expended to raise it. When lowering the object, the work done by the hand is considered negative because the force exerted is in the opposite direction of the displacement. This is due to the vector dot product, which results in a negative value when the force and displacement vectors are in opposing directions. Therefore, the work done while lowering the object is indeed negative. Understanding these concepts is crucial in physics when analyzing work and energy.
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If I lift a mass up a certain distance and it creates a positive work quantity, then when I lower the object back down does the work become negative?

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Yes, the work done by your hand on the block as you support it while lowering it is a negative quantity.

(The vector dot product of a force in one direction and a displacement in the opposite direction is negative)
 

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