Equilibrium Pulley Tension Problem

Click For Summary
SUMMARY

The discussion revolves around solving the equilibrium pulley tension problem involving weightless and frictionless pulleys with a gravitational acceleration of 9.8 m/s². The user attempts to calculate the tensions T2 and T3, concluding with an incorrect total tension T of 24 N. The correct approach involves recognizing that tension forces pull away from the objects they act upon, necessitating a correction in the signage of the equations used to solve for the tensions.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Basic principles of equilibrium in physics
  • Knowledge of tension in pulley systems
  • Ability to manipulate algebraic equations
NEXT STEPS
  • Review the concept of tension in pulley systems
  • Study equilibrium conditions in static systems
  • Learn about free-body diagrams for analyzing forces
  • Practice solving similar problems involving multiple pulleys
USEFUL FOR

This discussion is beneficial for physics students, educators, and anyone interested in mastering the principles of tension and equilibrium in mechanical systems.

livewire852
Messages
3
Reaction score
0
Hello! I've been trying to understand this one for a while now, and think there might be a general mental block with regards to pulleys, tension etc.

Homework Statement


http://s3.photobucket.com/albums/y5...tions/?action=view&current=pulleyquestion.jpg
Question: "The system is in equilibrium and the pulleys are weightless and frictionless. The acceleration of gravity is 9.8 m/s^2. Find the tension T. Answer in units of N."


Homework Equations


w=mg?
Not really sure about these


The Attempt at a Solution


Right, so so far I've tried solving for T2 and T3 separately then solving the big T. Since the pulley on the right has only the 14N mass acting on it, then T2 should be 14N/2, or 7N right? Then for the second pulley on the left, I got
T3 + T2 - 19 = 0, which would make T3 = 12. Presumably this would make T = 24 N, but this isn't correct!
I imagine I am making some heinous oversight or massive assumption. Thanks in advance!
 
Physics news on Phys.org
livewire852 said:
Hello! I've been trying to understand this one for a while now, and think there might be a general mental block with regards to pulleys, tension etc.

Homework Statement


http://s3.photobucket.com/albums/y5...tions/?action=view&current=pulleyquestion.jpg
Question: "The system is in equilibrium and the pulleys are weightless and frictionless. The acceleration of gravity is 9.8 m/s^2. Find the tension T. Answer in units of N."


Homework Equations


w=mg?
Not really sure about these


The Attempt at a Solution


Right, so so far I've tried solving for T2 and T3 separately then solving the big T. Since the pulley on the right has only the 14N mass acting on it, then T2 should be 14N/2, or 7N right?
right!
Then for the second pulley on the left, I got
T3 + T2 - 19 = 0, which would make T3 = 12. Presumably this would make T = 24 N, but this isn't correct!
Tension forces always pull away from the objects on which they act. Correct your error in signage.
 

Similar threads

  • · Replies 22 ·
Replies
22
Views
1K
  • · Replies 3 ·
Replies
3
Views
4K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 12 ·
Replies
12
Views
3K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 13 ·
Replies
13
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
1
Views
2K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 4 ·
Replies
4
Views
3K