Pulling on a bar-what forces are in action?

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The discussion centers on the forces at play when pulling on a bar without accelerating, specifically referencing Newton's second law. The net forces equal zero, indicating a balance of forces: the force exerted by the bar on the hand, the gravitational force downward, and the normal force plus static friction acting upward and to the left. The confusion arises regarding the identification of the counterforce, which is clarified as the static friction between the feet and the ground, not the hand's force on the bar. Understanding these forces is essential for grasping the principles of static equilibrium in physics.

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I aw wondering, if I pull on a bar but do not accelerate, according to Newton's second law, the net forces equal zero,but what forces exactly are keeping me from accelerating? I know that there's the force of the bar on my hand, but I asked my teacher and she said that the other force is NOT the force of my hand on the bar. Any ideas?
 
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That question is not very clearly stated, so I'm not even sure what the question is. But I'll guess. The short answer is inertia. The bar exerts interia on your trying to accelerate it, so if you don't accelerate it, either its firmly fixed or you're firmly weak.

As far as the counterforce NOT being your hand on the bar, that makes no sense. You defined the system that way. I'd ask the "teach" for greater clarification. Good luck!
 
Oaxgc said:
I aw wondering, if I pull on a bar but do not accelerate, according to Newton's second law, the net forces equal zero,but what forces exactly are keeping me from accelerating? I know that there's the force of the bar on my hand, but I asked my teacher and she said that the other force is NOT the force of my hand on the bar. Any ideas?
I guess you stand on the floor and pull the bar horizontally? The other force acts on your feet horizontally (static friction).

There are 3 forces acting on you, which as vectors add to zero:
- Right from the bar
- Down from gravity
- Up & Left from the ground (Normal force & static friction component)
 

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