Force is a push or pull exerted on a body. It is a fundamental concept in physics that refers to an interaction which often tends to change the motion of an object.
Force is a vector quantity which means it has both magnitude and direction. Force is usually measured in Newton.
The force acting on a body causes any of the following:
- Changes the motion of the body.
- Retard the motion of the body.
- Balance the forces already acting on a body.
- Induce internal stresses on the body.
In order to understand more about the forces, we must understand the characteristics of force.
The following are the characteristics of the force:
Characteristics of force
Magnitude and direction: The magnitude is the value of the force. The effect of the force depend on how stronger value it has and the direction which it acts.
Point of application: The specific location where force is applied on a object is crucial as it can affects the objects rotation and translation.
In the above example imagine the block is fixed at a point in the center. The point of application of force at top corner tends to rotate the block(Rotation).
If no fixed point and block placed in ground the force acting on the left side of the block tend to move the block to the xy direction(Translation).
Line of Action: The line along which the force acts is called the line of action. It extends infinitely in both directions through the point of application.
Resultant Force: When multiple force acts on a object, their combined effect is represented by a single force called resultant force. This is the vector sum of all individual forces.
Balanced and unbalanced forces:
Forces are balanced when their resultant force is zero,leading to no change in objects motion.
Unbalanced forces result in a non zero resultant force, causing a change in motion.
Effects of Forces on a object
The forces acting on a object causes an object to :
- Accelerate(change in speed or direcion)
- Decelerate(reduce speed)
- change shape(Deformation)
- Remain stationary
- Rotate(if force creates a torque)
Types of forces
The common types of forces include gravitational forces, electromagnetic force, frictional force, tension force normal force and applied force.
Unit of force
Mathematically force is defined by newtons second law of motion.
F = ma.
where F is the force applied to the object. m is the mass of the object and a is the acceleration produced by the force.
I t is measured in Newton represented by N.