Lesson 5, Topic 2
In Progress

# Condition of Equilibrium Under the Action of Non-Parallel Coplanar Forces

Lesson Progress
0% Complete

### Topic Content:

• Condition of Equilibrium Under the Action of Non-Parallel Coplanar Forces

The conditions of equilibrium under the action of non-parallel coplanar forces are:

1. Forces: The vector sum of all the forces acting on a body must be zero i.e.

(i) The algebraic sum of the horizontal components must be zero i.e.Â âˆ‘Fx = 0

(ii) The algebraic sum of the vertical components of the forces must be zero i.e.Â  âˆ‘Fy = 0

2. Moments:  The algebraic sum of the moments of all the forces about any axis perpendicular to the plane of the forces must be zero.

### Example 5.2.1:

In the diagram below an object of mass 500 kg is kept in equilibrium by three cables. Find the tension in each of the three cables. (g = 9.8 ms-2)

Solution:

Tension in cable 3 can be found easily

T3 = mg

âˆ´ T3 = 500 Ã— 9.8 = 4900 N (in the negative direction)

To find T1 and T2, since the object is in equilibrium âˆ‘Fx = 0 and âˆ‘Fy = 0

The horizontal component of T1 = T1X

The vertical component of T1 = T1Y

The horizontal component of T2 = T2X

The vertical component of T2 = T2Y

The horizontal component T1x = T1 cos 30Âº (Note: this is moving in the negative direction)

You are viewing an excerpt of this Topic. Subscribe Now to get Full Access to ALL this Subject's Topics and Quizzes for this Term!

Click on the button "Subscribe Now" below for Full Access!

### Subscribe Now

Note: If you have Already Subscribed and you are seeing this message, it means you are logged out. Please Log In using the Login Button Below to Carry on Studying!