Moment of a Force A moment of a force is a measure of the "torque" generated by that force about an axis of rotation. It is defined as the product of the...
A moment of a force is a measure of the "torque" generated by that force about an axis of rotation. It is defined as the product of the magnitude of the force and the distance from the axis of rotation to the line of action of the force.
Mathematically:
where:
M is the moment of force in newton-meters (Nm)
F is the magnitude of the force in newtons (N)
d is the distance from the axis of rotation in meters (m)
Moment of force is a scalar quantity, meaning it has only magnitude and no direction.
Example:
Consider a force of 10 N applied 0.5 m from the center of a rigid body. The moment of force would be:
This means that the body will rotate around its center through an angle of 30 degrees when the force is applied.
Additional Notes:
The moment of force is also equal to the product of the magnitude of the force and the angular distance from the axis of rotation to the line of action of the force.
The moment of force can also be calculated for a single force acting on an object by dividing the force by the distance from the axis of rotation.
The moment of force is a conserved quantity, meaning its magnitude remains constant throughout an equilibrium motion.
Moment of force can be used to analyze the rotational motion of objects subjected to external forces