The moment of a force, also known as torque, is a measure of the tendency of a force to rotate an object about an axis or pivot point.
Mathematically, it is defined as the product of the magnitude of the force and the perpendicular distance from the axis of rotation to the line of action of the force.
The formula for calculating the moment (torque) of a force is:
Moment = Force x Perpendicular distance from the pivot
The unit of torque is typically newton-meters (Nm) .
The moment of a force is a measure of its tendency to cause a body to start to .
Example 1
Example 1
In this example there is a 5kg mass, which exerts a 50N force perpendicular (at right angles) to the linear distance from the pivot.
50N x 5m = 250 Nm
The moment of a force is calculated by multiplying the magnitude of the force by the distance from the point of rotation.
Rotational Equilibrium
Rotational equilibrium occurs when the sum of the torques (moments) acting on an object is zero. This means that there is no net torque causing the object to rotate.
In rotational equilibrium, the clockwise torques must be balanced by the counterclockwise torques. This ensures that the object remains stationary or continues to rotate at a constant angular velocity.
Example 2
In this example the seesaw is in equilibrium because the two opposing moments are equal and therefore cancel each other out.
In equilibrium, the sum of all moments acting on a body is equal to .
