Why Does Calculating Tension in Multiple Blocks Require Different Forces?

  • Thread starter Thread starter arianemati
  • Start date Start date
  • Tags Tags
    Law
Click For Summary
SUMMARY

The discussion focuses on calculating tension in a system of blocks using Newton's first law. Specifically, the tension (T) in the rope connecting block A to block B is determined by the friction force (Ra), leading to the equation T = Ra. In contrast, when calculating the tension (T2) in the rope connecting block B to block C, all forces acting on block B must be considered, resulting in the equation T2 = P + Rb + Ra. This distinction highlights the importance of accounting for all relevant forces in multi-block systems.

PREREQUISITES
  • Understanding of Newton's laws of motion
  • Basic knowledge of tension and friction forces
  • Familiarity with free body diagrams
  • Concept of equilibrium in static systems
NEXT STEPS
  • Study advanced applications of Newton's laws in multi-body systems
  • Learn how to construct and analyze free body diagrams
  • Explore the effects of friction in dynamic systems
  • Investigate tension calculations in pulleys and complex mechanical systems
USEFUL FOR

Students and professionals in physics, engineering, and mechanics who are looking to deepen their understanding of tension calculations in systems involving multiple blocks and forces.

arianemati
Messages
4
Reaction score
0
Homework Statement
Newtons 1st law, constant velocity
Relevant Equations
Sum F = 0
If I want to find the tension in the rope that connects block A and B. I can apply Newtons first law.

Sum of all forces in opposite direction equals 0.

The forces that work on block A is Friction (Ra) and the force on the rope that pulls the block towards the right (T) So we get T-Ra = 0 and therefore T=Ra. We don't look at the force T2 or mcg, or the friction working on block B.

So my question is. If we on block A only use the first force to the right and the first force to the left. (T-Ra) to find the tension in the rope connecting A and B . When we find the tension in the rope (T2) connecting B and C. Why do we have to calculate all forces that work to the left (T2 = P+Rb+Ra) instead of T2=P+Rb ?
 

Attachments

  • IMG_78D49614C795-1.jpeg
    IMG_78D49614C795-1.jpeg
    68.6 KB · Views: 202
Physics news on Phys.org
You forgot the problem statement. What is the exercise ?
 
BvU said:
You forgot the problem statement. What is the exercise ?

Nevermind. I think I got it :)
 

Similar threads

Mechanics question: Three masses and a pulley on a tabletop
  • · Replies 3 ·
Replies
3
Views
1K
Rocket + Connected Body Dynamics problem
  • · Replies 47 ·
2
Replies
47
Views
3K
Newton's law problem: Helicopter lifting a box with a rope
  • · Replies 5 ·
Replies
5
Views
3K
Pulley with friction, how to get the friction in the pulley?
  • · Replies 23 ·
Replies
23
Views
3K
Calculating acceleration of a prism and block connected to a wall through a rope and pulley
  • · Replies 4 ·
Replies
4
Views
986
Struggling to make relation between elastic force and height
  • · Replies 11 ·
Replies
11
Views
1K
Static Friction Required to Keep the System from Moving (Two Boxes)
  • · Replies 16 ·
Replies
16
Views
3K
Why are the forces on torque tension and not the weight of the mass?
  • · Replies 7 ·
Replies
7
Views
2K
Newton's law problem: Pushing 2 stacked blocks on a horizontal table
  • · Replies 13 ·
Replies
13
Views
3K
Finding the work done by a block
  • · Replies 4 ·
Replies
4
Views
3K