Is Net External Work Only the Work Done by the Hand in a Spring System?

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Net external work in the discussed spring system is defined as the work done by the hand on block A, calculated as W = F*D, where F is the force applied and D is the distance moved. The wall does not contribute to the work since it does not move, resulting in zero work done by the wall on the spring. Consequently, the net external work on the system, which includes both block A and the spring, is solely attributed to the work performed by the hand. If the wall did not exert a force back, the hand would be unable to perform any work. Thus, the net external work is indeed just the work done by the hand.
kykk
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Quick question about net external work

Got a block (A) attach to Spring which attach to a Wall
Hand pushes A toward the wall which compress the Spring

So hand is doing positive work on A, W = F*D, work is whatever force by hand times distance..
But work done ON the spring BY the wall is zero right? wall didn't move, spring didn't move?

if zero for the wall, then the net external work on the system (block A + Spring) is just the work done by hand, the same W = F*D ?
 
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Hi kykk.

kykk said:
But work done ON the spring BY the wall is zero right? wall didn't move, spring didn't move?
That sounds right.

if zero for the wall, then the net external work on the system (block A + Spring) is just the work done by hand, the same W = F*D ?
Yes. If the wall hadn't pushed back, the hand would have had nothing to push against and could not have done any work here.
 
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