If a body is in rotational equilibrium under the action of three force , the lines of action of the three forces must be either concurrent of parallel.
A system of three forces in equilibrium must be coplanar and either be concurrent or be parallel. Let us assume that the two of the forces F1 and F2 intersect at a point A. The resultant of these two forces is given by, The third force is equal and opposite of this force.
A particle is in equilibrium if it is stationary or it moves uniformly relative to an inertial frame of reference. A body is in equilibrium if all the particles that may be considered to comprise the body are in equilibrium.
One can study the equilibrium of a part of the body by isolating the part for analysis. Such a body is called a free body. We make a free body diagram and show all the forces from the surrounding that act on the body. Such a diagram is called a free-body diagram. For example, consider a ladder resting against a smooth wall and floor.
Three forces are acting on the ladder. Gravitational pull of the earth (weight), W of the ladder, reaction of the floor R2 and reaction of the wall R1 .
When a body is in equilibrium, the resultant of all forces acting on it is zero. Thus that resultant force R and the resultant couple MR are both zero, and we have the equilibrium equations
A particle is in equilibrium if it is stationary or it moves uniformly relative to an inertial frame of reference. A body is in equilibrium if all the particles that may be considered to comprise the body are in equilibrium.
One can study the equilibrium of a part of the body by isolating the part for analysis. Such a body is called a free body. We make a free body diagram and show all the forces from the surrounding that act on the body. Such a diagram is called a free-body diagram. For example, consider a ladder resting against a smooth wall and floor.
Three forces are acting on the ladder. Gravitational pull of the earth (weight), W of the ladder, reaction of the floor R2 and reaction of the wall R1 .
When a body is in equilibrium, the resultant of all forces acting on it is zero. Thus that resultant force R and the resultant couple MR are both zero, and we have the equilibrium equations
