How to calculate the Resultant force due to a Lever arm?

Click For Summary

Homework Help Overview

The discussion revolves around calculating the resultant force due to a lever arm, specifically focusing on the mechanics of a rigid body supported by a hinge. Participants are examining the setup and the forces involved, particularly in relation to torque and equilibrium.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants are clarifying the setup of the lever arm, questioning the nature of the hinge and the constraints on motion. There are discussions about the distinction between mass and force, and the implications for calculating forces at specific points. Suggestions include creating a coordinate system to analyze forces and moments.

Discussion Status

The discussion is ongoing, with participants providing clarifications and suggestions for approaching the problem. Some guidance has been offered regarding the need to distinguish between mass and force, and the importance of considering equilibrium in the analysis.

Contextual Notes

There are constraints related to the definitions of mass and force, as well as the requirement for participants to post their attempts in accordance with forum rules. The original poster has provided an illustration of their attempt to solve the problem.

JPakt
Messages
3
Reaction score
0
Homework Statement
Need help to find the resultant force at the Point "C" on an object, when a 230-gram force applied at Point "A" which is hinged at point "B".
Relevant Equations
F1.x1 = F2.x2
1581461413877.png
 
Physics news on Phys.org
The set up needs more description.
Does the blue line represent a rigid, but bent, arm, or two arms hinged independently at B?
Is B free to move around in space or constrained somehow?
Are there constraints on A's motion?

Also, you need to post an attempt, per forum rules.
 
  • Like
Likes   Reactions: JPakt and gneill
Thanks for your response.

- 2 Blue Line represents a rigid body
- Point B is hinge support which allows the rotation in an anticlockwise direction and applies force in the direction highlighted at point "C" on a spring.
- Point A represents the CG of the body

Hope I answered your questions.

Please find the attachment which illustrates my attempt to solve the problem.
 

Attachments

  • Moment arm.JPG
    Moment arm.JPG
    42.6 KB · Views: 237
JPakt said:
Hope I answered your questions.
Yes, thank you.
The mass is 230gm. That is a mass, not a force, which makes your equations for forces incomplete.
Other than that, your method works, but there is an easier way. You do not need to find F1 to find the torque exerted by the weight. Likewise at the other end.
 
Got it. Thanks for your comments.

I appreciate your inputs
 
You need to determine whether or not those 230 grams are mass or gram-force, in order to provide a proper value for horizontal force at point C.
I recommend creating an orthogonal coordinate system (X-Y axes) with the same orientation of the two forces in the problem.
Disregard the shape and angles of the object, just consider it a disc that pivots around point B.
Then, compute all the forces and moments around the pivot point, considering that the object is in equilibrium.
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
2K
Replies
19
Views
2K
  • · Replies 8 ·
Replies
8
Views
3K
Replies
3
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 18 ·
Replies
18
Views
3K
Replies
23
Views
2K
  • · Replies 5 ·
Replies
5
Views
3K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 8 ·
Replies
8
Views
2K