Equilibrium. How to solve for four variables?

Click For Summary
SUMMARY

The discussion focuses on solving for four variables related to a uniform beam supported by a wire and hinged to a wall. The beam weighs 288 N and is 3.12 feet long, with the wire making 30° angles with both the beam and the wall. Key equations used include the sum of forces and torques, specifically ΣF=0 and ΣTorque=0. The solution involves breaking the problem into parts, calculating torque components, and applying equilibrium conditions to find the tension in the wire and the hinge forces.

PREREQUISITES
  • Understanding of static equilibrium principles
  • Knowledge of free body diagrams
  • Familiarity with torque calculations
  • Basic trigonometry, particularly sine and cosine functions
NEXT STEPS
  • Learn how to construct and analyze free body diagrams for static systems
  • Study torque calculations in detail, focusing on the perpendicular components of forces
  • Explore the principles of static equilibrium in multi-force systems
  • Practice solving problems involving tension and forces in beams and cables
USEFUL FOR

Students in physics or engineering courses, particularly those studying statics, mechanics, or structural analysis. This discussion is beneficial for anyone looking to understand the forces acting on beams and the application of equilibrium conditions.

moose726
Messages
3
Reaction score
0

Homework Statement


One end of a uniform beam weighing 288 N and 3.12 feet long is attached to a wall with a hinge. The other end is supported by a wire making equal angles of 30° with the beam and wall.

(a) Find the tension in the wire.

(b) What is the horizontal component of the force of the hinge on the beam?

(c)What is the vertical component of the force of the hinge on the beam?

Homework Equations


\SigmaF=0
\SigmaTorque=0

The Attempt at a Solution


I drew a free body diagram of the beam and the components of the forces from tension and the hinge. From this I got four equations:
\SigmaFx = Fx-Tx = 0
\SigmaFy = Fy+Ty-mg = 0
\Sigma Torque = 118.5+.4754Tx-.823Ty=0 (T is tension, this torque is with the hinge as the origin.)
Fy=Fxtan(30)
I'm not sure how to solve for each variable with these equations.
 
Physics news on Phys.org
The easiest way to think about this is to break it into parts. Instead of solving for multiple unknowns just solve for part a.

The vertical component of tension must be perfectly balanced by the vertical component of the torque of the beam. Same goes for the horizontal tension.

You can calculate the torque in the x and y directions and then you have two equations with two unknowns.
 
Take the components of tension T along and perpendicular to the beam. Similarly take the components of the weight of the beam, which acts at the center of the beam.
The perpendicular components contribute to the torque, while components along the beam does not contribute to the torque.
Apply the condition for equilibrium and solve for T.
Convert the unit of length from ft to m.
 

Similar threads

  • · Replies 6 ·
Replies
6
Views
4K
Replies
8
Views
6K
  • · Replies 9 ·
Replies
9
Views
5K
  • · Replies 3 ·
Replies
3
Views
2K
Replies
6
Views
2K
  • · Replies 18 ·
Replies
18
Views
3K
  • · Replies 10 ·
Replies
10
Views
6K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 4 ·
Replies
4
Views
4K
Replies
4
Views
2K