Question About Work-Energy Theorem

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The Work-Kinetic Energy Theorem states that the work done on an object is equal to the change in its kinetic energy, expressed as W=ΔK. In problems involving multiple forces, it is valid to sum the work done by all forces, leading to the equation ∑W = ΔK. This aligns with Newton's second law, where the net force (F) acting on an object determines its acceleration (a). Consequently, the net work (W) done on the object corresponds to the change in kinetic energy. Understanding this relationship clarifies the application of the theorem in complex scenarios.
dlacombe13
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Very simple question. So I am on a homework problem, and I want to make sure that I am using this theorem correctly. My book states that the Work-Kinetic Energy Theorem is:

W=ΔK

Now the solution to this problem involved multiple forces and thus each force is doing work. So my question is, is it legal to say that:

∑W = ΔK
 
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dlacombe13 said:
Very simple question. So I am on a homework problem, and I want to make sure that I am using this theorem correctly. My book states that the Work-Kinetic Energy Theorem is:

W=ΔK

Now the solution to this problem involved multiple forces and thus each force is doing work. So my question is, is it legal to say that:

∑W = ΔK

Yes. Precisely.
 
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Likes vanhees71 and dlacombe13
Thank you, the problem makes complete sense to me now!
 
In Newton's second law, F = ma, F is always the net force acting on an object. Therefore, in the work-energy theorem, W is always the net work done on the object.
 

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