Can someone check if this forces problem on an incline

  • Thread starter Thread starter Blockade
  • Start date Start date
  • Tags Tags
    Forces Incline
Click For Summary

Homework Help Overview

The discussion revolves around a forces problem involving a block on an incline, where participants are examining the setup and calculations related to the forces acting on the block and the incline.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants question the independence of the force P from the angle θ and suggest drawing free body diagrams for clarity. There is also a focus on identifying the forces acting on both the block and the plank separately, with some confusion regarding the mass used in calculations.

Discussion Status

The discussion is ongoing, with participants providing hints and suggestions for clarification. There is an indication that the original poster may revisit their calculations based on feedback received.

Contextual Notes

There are mentions of specific forces such as tension and friction, as well as a potential misunderstanding regarding the mass of the block. The original poster expresses uncertainty about their initial setup and calculations.

Blockade
Messages
68
Reaction score
0
To me the force P that pulls the bottom block up the incline seems a little low. Can someone confirm with my setup and work in brown is correct? Thank you.

Problem:
8eea061f2a.jpg


Work:
4c89ea0207.png
 
Physics news on Phys.org
Would you expect P to be independent of ##\theta## ?
Draw a free body diagram for each of the blocks separately.
And I see one of the two blue arrows (the most illegible one :smile:) can't be right.
 
BvU said:
Would you expect P to be independent of ##\theta## ?
Draw a free body diagram for each of the blocks separately.
And I see one of the two blue arrows (the most illegible one :smile:) can't be right.

ΣFxA : P - T - (3mgsinθ) - μk mgcosθ= 0

That was your hint right XD.
 
Blockade said:
ΣFxA : P - T - (3mgsinθ) - μk mgcosθ= 0

That was your hint right XD.
How about clearly stating what forces act on the plank and what forces act on the block - separately.

The mass of the block is 2m, right. Why do you have 3m ?

The plank acts on the block via friction and via the tension in the cord.
 
4
SammyS said:
How about clearly stating what forces act on the plank and what forces act on the block - separately.

The mass of the block is 2m, right. Why do you have 3m ?

The plank acts on the block via friction and via the tension in the cord.

I will redo the problem and post it back up. Thanks for you input.
 

Similar threads

Block and pulley on movable incline
  • · Replies 2 ·
Replies
2
Views
2K
Work Done by Friction & Gravity on Incline: Explained
  • · Replies 7 ·
Replies
7
Views
8K
How can we model a rolling truck on an incline using rotational motion analysis?
  • · Replies 24 ·
Replies
24
Views
3K
Block at rest on an inclined surface
  • · Replies 36 ·
2
Replies
36
Views
6K
Difficulty in deciding when to apply work energy theorem
  • · Replies 2 ·
Replies
2
Views
2K
A frictionless incline with a block sliding down it....
  • · Replies 2 ·
Replies
2
Views
3K
Find the mass of a block on an inclined pulley
  • · Replies 3 ·
Replies
3
Views
2K
Physics Homework -- block pressed against a wall is sliding....
  • · Replies 4 ·
Replies
4
Views
4K
Solving Incline Problem with Normal Force: 39.36
  • · Replies 13 ·
Replies
13
Views
2K
Inclined Plane Forces - with a twist
  • · Replies 2 ·
Replies
2
Views
2K