Equilibrium of two forces

Resultant force

Resultant force

is a virtual force whose action is equal to the combination of all the forces applied simultaneously to an object.

The resultant force is calculated depending on:

When two forces are applied in the same direction, along the same line of action (vertically or horizontally), the resultant force is the sum of the two (Figure 3.21).

When two forces are applied along the same line of action but in opposite directions, the resultant force is the difference between the two (Figures 3.22 and 3.23).

Equilibrium of two forces…

is achieved when the resultant force is zero. The motion of the object therefore remains constant.

What is a resultant force?

It is very common for an object to be subjected to several forces at the same time. To determine the combined effect of a number of forces acting simultaneously on an object, we calculate the resultant force, or net force.