Formula of Resultant Force
If one force is acting perpendicular to another, the resultant force is determined by using the Pythagorean theorem. The Resultant force formula is given by,
FR = F1 + F2 + F3
Where
F1, F2, F3 are the three forces acting in the same direction on an object.
Solved Example of Resultant Force
Example 1
Determine the FR when three forces such as 80 N, 100 N, and 30 N are acting on an object simultaneously and 30 N force is opposite to the other two forces.
Solution:
Given:
F1 = 80 N
F2 = 100 N
F3 = -30 N
F3 is a negative value because it is acting opposite to the other two force
The formula for resultant force is
FR = F1+F2+F3
FR = 80 + 100 – 30
FR = 150 N