Rod and we pull one end of it with a 10N force

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    Force Pull Rod
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Discussion Overview

The discussion revolves around the mechanics of a rod being pulled at one end with a 10N force while the other end is fixed. Participants explore concepts related to force, acceleration, net force, and tension in the context of static equilibrium.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant questions whether it is correct to say that a 10N force is applied to the rod since there is no acceleration observed.
  • Another participant argues that the fixed end of the rod applies a normal force of 10N to whatever it is fixed to, resulting in a net force of zero on the rod.
  • A different participant clarifies that a net force is required for acceleration, suggesting that the initial statement about force application is misleading.
  • One participant points out that the presence of opposing forces at the ends of the rod creates tension within the rod, despite the lack of net force.
  • Another participant uses the example of a stationary book on a table to illustrate that forces can exist without resulting in net force, emphasizing that forces are always present even in static situations.
  • A later reply introduces the idea that gravity creates a pressure force from the book on the table, referencing Newton's third law regarding action and reaction forces.

Areas of Agreement / Disagreement

Participants express differing views on the nature of force and acceleration, with some emphasizing the distinction between applied forces and net forces, while others highlight the existence of forces in static scenarios. The discussion remains unresolved regarding the interpretation of force application in the given problem.

Contextual Notes

Participants reference concepts from Newtonian mechanics, but there are unresolved assumptions regarding the definitions of force and net force, as well as the implications of static versus dynamic conditions.

chandran
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an example problem statement
there is a rod and we pull one end of it with a 10N force with the other end fixed.

recall that a force acts on a body only when it accelerates. But in the above problem is it correct to say that 10N force is applied (i see
that there is no force applied on it since there is no acceleration of the rod)
 
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If the other end is fixed, then it will apply a normal force of magnitude 10N to whatever it is fixed to. It's net force is zero.
 
chandran said:
recall that a force acts on a body only when it accelerates.
This isn't true. A NET force acts on a body if it accelerates. Or more properly, an object will accelerate only if it has a net force acting on it.
 
There is no net force. Because there are forces, acting in opposite directions at the ends of the rod, there is tension in the rod.
 
On Earth a stationary book on a tabletop (in a vacuum blah blah blah) is still being pulled down by a force, namely gravity but that is balanced by the normal force of the table pushing up on the book. So there are no net forces, like the others have said, but there are forces. Forces are ubiquitous and invisible.
 
Nope.Gravity determines a pressure force by the book acting on the table.The reaction force is its pair in the spirit of Newton's III-rd principle.

Daniel.
 

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