Relative Work - not sure what it means-

AI Thread Summary
In the discussion, participants analyze the work done on a block by two individuals pushing in opposite directions on a frictionless surface. It is established that the force exerted by person 1 is greater than that of person 2, resulting in person 1 doing more work on the block. The conversation explores the implications of the block coming to rest, suggesting that person 2's force eventually counteracts person 1's, leading to a total work of zero when kinetic energy dissipates. There is confusion regarding the phrasing of the question about relative work, with participants questioning how to articulate the relationship between the work done by each person. Ultimately, the discussion emphasizes that all work is relative, as absolute values cannot be calculated in this scenario.
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Homework Statement



Two people push in opposite directions on a block that sits atop a frictionless
surface (The soles of their shoes are glued to the frictionless surface). If the
block, originally at rest at point P, moves to the right without rotating and ends
up at rest at point Q, describe qualitatively how much work is done on the
block by person 1 relative to that done by person 2?

https://docs.google.com/viewer?pid=bl&srcid=ADGEESibEj7pzQOnOXVNPdE4L1V9YvbZjDsvpoIYd9X36QE73jfnjn3DCgrDR-bbW3An133sPXBv0FACZ65q9TpkFy0t6LlDRzoc3OuWYQmxt4BP_ek_7CKff7heIXLJOepSzUmLmkaW&q=cache%3Apu-zuL8y6zkJ%3Aocw.mit.edu%2Fcourses%2Fphysics%2F8-01sc-physics-i-classical-mechanics-fall-2010%2Fwork-and-energy%2FMIT8_01SC_problems11.pdf%20how%20much%20work%20is%20done%20on%20the%20block%20by%20person%201%20relative%20to%20that%20done%20by%20person%202%3F&docid=c21a27004575c8d09fb3d870f827860c&a=bi&pagenumber=1&w=800

Homework Equations



W = F*dx

The Attempt at a Solution



I could not make up my mind with the question, what it asks. I said from the direction of the motion we know F1>F2 and thus W1>W2. And also W1 is positive whereas W2 is negative. But what else should i say? Shall i say total work is W1-W2 or something like that ?
 
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A strange question! I'm wondering why the motion stops. Does person 2 start pushing harder, to overcome F1 and decelerate the block? Maybe it hits his glued-down shoes.
Anyway, the total work is ultimately zero when the kinetic energy disappears. Before that, all is as you said.
 
Can you please express your opinion about the last sentence of the question? What does it imply by saying "by person 1 relative to that by person 2?" I mean it does not ask about total work, but I feel uncomfortable that I think I am not answering properly if I say things only in post 1.
Thanks!
 
Everything you say is "relative", since you have no way to calculate any absolute numbers.
I'm just thinking of some qualifiers, like F1 > F1 at some point because the box moves to the the right. One does some work on the box and on two. Two absorbs all that work eventually, some gradually, the last of it when the box hits his foot and loses its kinetic energy.
 
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