Power supplied holding a mass suspended in air

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The discussion revolves around the concept of power required to hold a mass suspended in air, highlighting the confusion between power, work, and energy. It emphasizes that while power is defined as the product of force and velocity, no work is done when an object is stationary, leading to the conclusion that power is not needed to maintain an object in a static position. However, the physical exertion involved in holding a weight, such as a 50-kilogram object, is acknowledged, despite no mechanical work being performed. The conversation also touches on the inefficiency of the human body, which requires a constant energy supply to maintain muscle contraction, contrasting with the static support provided by an inanimate object like a table. Ultimately, the distinction between physical work and the energy required for muscle function is clarified.
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A problem I thought would be very simple, but can't seem to get very far with.

Taking equations from textbook: Fv = P . Nope because velocity is 0 however power cannot be 0.
Using suvat: W = Fs , s = ut + .5gt^t , therefore P = Fgt/2 , this seems like the equation for how power would increase as an object falls but not the power supplied to keep it suspended which I imagine would be constant with time.

So there it is, leaving me very fustrated as it seems like it must be really simple.
 
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Yes. Power=Fv and if it's velocity is changing(Accelerating at g), it's power should also change.I don't think I understood you r question clearly. We don't need power,not even energy to hold things in place. Consider a book lying at rest on a table. No work is done there.

Edit. You can still use that equation. Since no distance is traveled when it's suspended, you can just plug in 0 into s in P=Fs/t
 
Ok but hold 50 kilos out in front of you and tell my why its tiring but no work is being done?
 
piisexactly3 said:
Ok but hold 50 kilos out in front of you and tell my why its tiring but no work is being done?
Tiring and work done are two different things.
Our bodies are not efficient. We even get tired sitting somewhere without moving.
Muscle cells in our body need constant supply of energy to stay contracted(Which keeps things lifted up) On the other hand, the table does not deform to keep things above the ground.
 
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