\[F_1r_1=F_2r_2\]
Variables
M1moment produced by force F1 (N·m)
M2moment produced by force F2 (N·m)
F1first applied force (N)
F2second applied force (N)
r1perpendicular distance from pivot to F1 (m)
r2perpendicular distance from pivot to F2 (m)
Description
What is this formula?
This formula represents the moment balance condition for static equilibrium. A rigid body remains in rotational equilibrium when the clockwise and counterclockwise moments about a pivot are equal.
When to use it
Use this formula to analyze levers, beams, supports, mechanical arms, brackets, and structures where rotation must be prevented.
Example
Data:
F1 = 120 N
r1 = 0.50 m
r2 = 0.75 m
Formula:
F2 = (F1*r1)/r2
Substitution:
F2 = (120*0.50)/0.75
Result:
F2 = 80 N
Applications
Statics
Beam analysis
Lever systems
Structural supports
Mechanical design