Is Holding a Weight at Arm's Length Considered Work?

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Holding a weight at arm's length does not constitute work in the physics sense, as work requires displacement. In this scenario, the boy holds a 40N weight stationary for 10 seconds, resulting in zero work done due to the lack of motion. Even if the weight were moved along a path and returned to the original position, the work done would still be zero because the net displacement remains unchanged. Therefore, the key factor is that without movement, no work is performed. This highlights the importance of displacement in defining work in physics.
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A boy holds a 40N weight at arm's length for 10s. His arm is 1.5m above the ground. The work done by the force of the boy on the weight he is holding. He would not be doing any work, because their is no motion and he is lifting it up.

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blackout85 said:
He would not be doing any work, because their is no motion and he is lifting it up.

A better way to state the answer would be to say that the displacement of the object is zero. For if he had taken the object along some crazy path and brought it back to where he started, the work done would still be zero, even though the object had moved.
 

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