Questions on work done and Newton's third law

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Discussion Overview

The discussion revolves around the concepts of work done in different scenarios of pushing and pulling a body, as well as the interaction of a hammer and nail with different materials, specifically wood and concrete, in the context of Newton's third law.

Discussion Character

  • Conceptual clarification
  • Debate/contested
  • Homework-related

Main Points Raised

  • One participant questions why the work done to push a body forward is perceived to be greater than pulling it backward and requests free body diagrams for both cases.
  • Another participant suggests that the inquiry may be related to homework and requests reasoning to assist further.
  • A participant asserts that their questions are self-generated and attempts to explain the interaction of a hammer and nail, proposing that the force exerted by the hammer on the nail is greater than the reaction force from the wooden wall, allowing the nail to penetrate wood but not concrete.
  • The same participant questions the differences in reaction forces between wood and concrete, seeking clarification on their explanation.
  • A later reply references another thread discussing the hammer and nail interaction with wood, suggesting that there may be existing discussions on the topic.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the explanations provided, and multiple competing views regarding the mechanics of work done and material interactions remain evident.

Contextual Notes

The discussion includes assumptions about the forces involved and lacks detailed free body diagrams or mathematical analysis to support the claims made. The differences in material properties between wood and concrete are not fully explored.

Misr
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Hello

1- work done to push body forward is greater than to pull body backward
what is the explanation for this?can you draw the two FBD in both cases ?



2- why is nail driven in wooden wall but not in the concrete wall ؟ I guess this is somehow related to Newton's third law

Thanks
 
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This seems like homework, you should provide some reasoning before we can help.
 
No that's not a homework ..I thought of these questions by myself.

as for the second question I'll tell you what I can imagine about this so far>>
the hammer applies a force on the nail by pulling on it
the nail has an equal reaction in the opposite direction
the nail applies force on the wall
the wall has an equal reaction in the opposite direction
the force of the hammer on the nail is greater than the reaction of the wooden wall so the nail is driven in wood but that's not the case in concrete>>
is my explanation true?if so why the reaction of the wall is different in wood and concrete?
I hope it's a good evidence that my questions are not for homework
 

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