What Force Is the Second Man Exerting on the Pulley?

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Homework Help Overview

The problem involves a fixed pulley system with a weight of 2N and two individuals exerting forces on either side of the pulley. The scenario is described as being in equilibrium, with the weight not moving. The original poster is trying to determine the force exerted by the second individual based on the force exerted by the first individual.

Discussion Character

  • Exploratory, Assumption checking

Approaches and Questions Raised

  • The original poster suggests that both individuals are exerting the same force (N), while a friend challenges this assumption. Some participants discuss the implications of having two ropes and the effect of angles on the forces involved.

Discussion Status

The discussion is ongoing, with participants exploring different interpretations of the forces at play. Some guidance has been offered regarding the tension in the ropes, but no consensus has been reached on the correct force exerted by the second individual.

Contextual Notes

Participants note that this scenario is not part of an assignment and is being discussed for fun, highlighting that they have not encountered a two-rope pulley system before.

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Homework Statement


There is a fixed pulley lifting weight of 2N. Attached to the weight there are two ropes. On the other side of the pulley there are two man standing, one of them just below the pulley and the other is further away (Illustrated). The weight is on balance, it is not moving. The man just below the pulley is using N force. What force the other man is using?


Homework Equations





The Attempt at a Solution


I argue that the other man is also using force N. But my friend is saying that he is not.

Any idea?

http://img396.imageshack.us/img396/38/pulleyuq5.th.jpg
 
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Hard to really help without giving you the answer (especially since there are only two choices!)
Hint - without friction, the tension in the rope is the same everywhere.
 
That's what I am thinking (If I guessed your answer correctly). If there was only one rope, then one man would have to use 2N force. But since there are two ropes, each has to pull with N. But my friend is arguing that we need to find the composite force for two, because the angles are different. Isn't it on the pulley the force 2N. One is using N and the other should use N as well?
This is not an assignment question by the way. Just for fun. We haven't seen any two rope pulleys before.
 
cansucan said:
Isn't it on the pulley the force 2N. One is using N and the other should use N as well?

The total combined load on the pulley would be 4N. For example, just imagine there was only one man pulling straight down on the rope on the other side with force 2N. Since the weight of the object is also 2N (straight down) and neither it nor the pulley are moving, the total reaction force on the pulley is 4N (draw a FBD and you see why if you don't already).

CS
 

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