How to setup linear force equations

Click For Summary

Discussion Overview

The discussion revolves around setting up linear force equations and torque balance for a system involving a planter and a rod, with a focus on understanding the forces and torques acting on the assembly. The context is primarily homework-related, as the original poster seeks assistance in solving a physics problem involving static equilibrium.

Discussion Character

  • Homework-related
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • The original poster describes a scenario involving a planter and a rod, detailing the masses and the angle of the rod with the wall.
  • They express uncertainty about how to set up linear force balance equations and torque balance, specifically asking for step-by-step guidance.
  • One participant suggests creating a sketch to visualize the forces acting on the system.
  • The original poster confirms they made a sketch and attempts to formulate the torque equation but remains confused about the initial linear force balance.
  • Another participant questions how the original poster could solve the torque equation without addressing the linear force balance first.

Areas of Agreement / Disagreement

Participants generally agree that a sketch is a useful tool for understanding the problem, but there is disagreement regarding the sequence of solving the equations, as the original poster struggles with the initial setup while another participant questions their approach.

Contextual Notes

The discussion highlights the original poster's lack of clarity on the foundational steps required to set up the equations, indicating potential gaps in understanding the relationships between forces and torques in static equilibrium.

Who May Find This Useful

Students working on static equilibrium problems in physics, particularly those involving forces and torques in systems with multiple components.

Superman
Messages
2
Reaction score
0
A planter of mass M=3kg is hung from a rod of mass m=1kg (3/4) of the way to the end. There is a horizontal wire attached to end of the rod pulling on it with tension Ft. The botom of the rod is hinged to the wall making an angle of 60 degrees with the wall. The assembly is to remain at rest.

  1. Setup the linear force balance equations, one along each axis you choose.
  2. Choose a pivot point and setup the torque balance about that point.
  3. Solve for the tension in the wire and the two force components at the hinge.
I know I am just blatantly asking a question but this is the final question on my homework and I do not have a single clue how to do it. If you could explain all the steps involved please.

for the first one I tried think of it like, going down but I don't know how to get that into equations

I really need some help on this
 
Physics news on Phys.org
Have you tried making a sketch of the planter, the rod, and the wire?
 
SteamKing said:
Have you tried making a sketch of the planter, the rod, and the wire?
Yes I made the sketch and I believe I have solved number 2

0=T[Lcos(theta)]-Mg[(3/4L)sin(theta)]-mg[(L/2)sin(theta)]

I still don't get number 1, do you know how to start number 1 once you have the sketch?
 
Did you show the forces acting on the rod on your drawing? You are given the mass of the rod and the planter, and the tension force in the wire is to be called Ft.

I don't understand how you could solve 2) without doing anything about 1).
 

Similar threads

  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 14 ·
Replies
14
Views
3K
  • · Replies 4 ·
Replies
4
Views
3K
  • · Replies 2 ·
Replies
2
Views
7K
  • · Replies 1 ·
Replies
1
Views
2K
Replies
12
Views
1K
  • · Replies 1 ·
Replies
1
Views
962
  • · Replies 3 ·
Replies
3
Views
3K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 14 ·
Replies
14
Views
3K