What is the net work done if an object is ?

AI Thread Summary
The net work done on the object is zero since it ends at the same height it started, despite being raised and lowered. The work done against gravity is calculated using the formula W=mgh, but without the mass, the exact value cannot be determined. Carrying the object horizontally does not change its potential energy, contributing no net work. The discussion emphasizes that while muscles exert effort, it does not result in a change in energy for the object. Therefore, the conclusion is that no net work is accomplished in this scenario.
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Homework Statement


What is the net work done if an object is raised 5m, carried horizontally 8m, lowered 2m, and then lowered 3m if there is no friction?


Homework Equations



W=F x d (force times distance)
work done overcoming gravity: W=mgh (mass times gravity times height)

The Attempt at a Solution


no idea! since we don't have the mass
 
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Those questions usually mean "work accomplished" rather than work "done". Your muscles would have to do some work to carry the mass, but that doesn't accomplish any change in the potential energy of the mass. In this case, the mass ends up at the same height as it started so no work is accomplished or stored in some useful form of energy.
 
net work done ON the object, not by your muscles.
 

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