Question about the significance of negative work

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Negative work is significant in understanding energy transfer between objects. When object A does work W on object B, it is equivalent to object B doing negative work -W on object A, indicating that energy is transferred from A to B. Scalars, including work, can be negative, reflecting the direction of energy transfer rather than a lack of magnitude. This concept aligns with the work-kinetic energy theorem, where the energy lost by one object corresponds to the energy gained by another. Clarifying these principles helps in grasping the physical significance of negative work.
Bipolarity
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I am having some trouble understanding the significance of negative work.

If the work that I do on object X is W, is it equivalent to saying that object X does work on me equal to -W ?

After all, work is scalar, so I can't fathom the physical significance of negative work.

Also, according to the work-kinetic energy theorem, due to the way in which work and kinetic energy are both defined, when I do work W on an object X, its kinetic energy increases by W and my energy decreases by W. Isn't that equivalent to saying that the object did work of -W on me, since at least in terms of kinetic energy the two are equivalent?

All help on my understanding of this concept is appreciated.

BiP
 
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Yes, what you stated is correct. The object does negative work on you. In a sense, the negative means that energy has been taken FROM the object in question (aka you). Remember, scalars can be negative! They just can't have direction. You might be confused because people in the early stages of physics courses will say that speed is a scalar and velocity is a vector, the former being unable to be positive, but this is specifically because of the way speed is defined; it is not a general property of scalars. I assume this is where the confusion lays?
 
Pengwuino said:
Yes, what you stated is correct. The object does negative work on you. In a sense, the negative means that energy has been taken FROM the object in question (aka you). Remember, scalars can be negative! They just can't have direction. You might be confused because people in the early stages of physics courses will say that speed is a scalar and velocity is a vector, the former being unable to be positive, but this is specifically because of the way speed is defined; it is not a general property of scalars. I assume this is where the confusion lays?

OK I get it so far. So if object A does work W on object B, then that is perfectly equivalent to saying that object B does work -W on object A?

BiP
 
That is correct.
 

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