A system of two bodies and wall

Click For Summary

Homework Help Overview

The discussion revolves around a physics problem involving two bodies and a wall, focusing on the forces acting on the bodies, their equilibrium states, and the implications of friction. Participants are exploring the dynamics of the system, particularly how the bodies interact with each other and the wall.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants discuss the normal force and applied forces, questioning the balance of forces acting on the bodies. There are inquiries about free body diagrams and the definitions of equilibrium. Some participants express uncertainty about the presence of friction and its implications on the motion of the bodies.

Discussion Status

The discussion is active, with participants raising multiple questions regarding the forces on each body and the conditions for equilibrium. Some guidance has been offered regarding the importance of free body diagrams, but there is no clear consensus on the interpretations of the problem or the assumptions being made.

Contextual Notes

There are references to potential ambiguities in the problem statement and the definitions used, such as the terms 'remain' and 'move together.' Participants are also considering the implications of different friction scenarios between the bodies and the wall.

  • #31
rudransh verma said:
There have to be relative motion between A and B for the friction to occur here.
No. That's only true for kinetic friction. I will add to @haruspex's comment...

Suppose a small parachute is attached to block B. Since A and B are pressed together, there could be enough static friction to prevent them sliding relative to each other. A and B would then fall together (in the same way as if they were stuck together).

Of course If you use a sufficiently big parachute and A is very heavy, then A will fall faster than B. Sliding occurs between A and B and the friction is kinetic.
 
Physics news on Phys.org
  • #32
Steve4Physics said:
No. That's only true for kinetic friction. I will add to @haruspex's comment...
O yeah! But there is also no static friction here because of the absence of any upward force. Both will fall as one system.
 
  • Like
Likes   Reactions: BvU and Steve4Physics
  • #33
rudransh verma said:
O yeah! But there is also no static friction here because of the absence of any upward force. Both will fall as one system.
Yes indeed! If you read through the previous posts, you will see that this is the message we have been trying to convey!
 
  • Like
Likes   Reactions: BvU

Similar threads

Equilibrium of Two Blocks in a Wall System: A FBD Approach
  • · Replies 19 ·
Replies
19
Views
2K
Problem in understanding angular momentum of a rigid body
  • · Replies 10 ·
Replies
10
Views
2K
How Does the Direction of Normal Contact Force Affect Shelf Stability?
  • · Replies 7 ·
Replies
7
Views
3K
When are reactive forces enough to support this body?
  • · Replies 14 ·
Replies
14
Views
1K
Undergrad Spring balance analysis from a system point of view
  • · Replies 24 ·
Replies
24
Views
2K
Calculating acceleration of a prism and block connected to a wall through a rope and pulley
  • · Replies 4 ·
Replies
4
Views
898
Book plots position & force on the same graph, still gets right answer
  • · Replies 8 ·
Replies
8
Views
1K
Which block reaches the wall faster?
  • · Replies 2 ·
Replies
2
Views
1K
Finding Radial Force from Free Body Diagram
  • · Replies 4 ·
Replies
4
Views
2K
Is the Normal Force on m2 Affected by Vertical Acceleration in Different Cases?
  • · Replies 1 ·
Replies
1
Views
1K