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

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    Force Pull Rod
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In the discussion, the application of a 10N force on one end of a fixed rod raises questions about the existence of force and acceleration. It is clarified that while there is no net force acting on the rod, forces are still present, creating tension within the rod due to opposing forces. The concept of force is distinguished from net force, emphasizing that forces can exist without causing acceleration. An analogy is made with a stationary book on a table, where gravitational force is balanced by the normal force, illustrating the presence of forces even in static situations. Overall, the conversation highlights the distinction between force and net force, reinforcing that forces are always at play, regardless of acceleration.
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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