Why Is the Work Done by Weight Zero When Pushing a Box Horizontally?

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The work done by the weight of a box when pushed horizontally is zero because the weight acts vertically downward, while the applied force and displacement are horizontal. Since work is calculated as the product of force and displacement in the direction of the force, the vertical weight does not contribute to work in this scenario. The work done by the 40N force is calculated as 80N, based on the formula work = force * distance. If the box were on an incline, the weight could influence the work done. Understanding the vector nature of force and displacement clarifies why the weight does not contribute to work in this case.
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Homework Statement


A box of weight 100N is pushed a distance or displacement of 2m with a force of 40N. What is the work done on the box by i) the weight and ii) by the 40N force?

Homework Equations


Work = force * distance

The Attempt at a Solution


i) The work done on the box by weight = 0 (if this is correct, why?)

ii) The work done on the box by the 40N force
Work = force * distance
Work = 40 * 2
Work = 80N
 
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Work, force, and displacement are vectors. Can you figure out "why" from there?
 
I'll just say ths, work done by weight is 0 because that fat box did not helping you out AT ALL

Now, if it was on an incline sliding down as you pushed it..
 
Jack21222 said:
Work, force, and displacement are vectors. Can you figure out "why" from there?

Let me see... weight is acting vertically downwards, while force and displacement are acting horizontally. Therefore the weight had no influence on the force and displacement?

cronxeh said:
I'll just say ths, work done by weight is 0 because that fat box did not helping you out AT ALL

Now, if it was on an incline sliding down as you pushed it..

Thanks very much, you made it clearer
 
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