What is force?
Force is an agent that changes the state of rest or motion in a body to which it is applied.
It produces or tends to produce, destroys or tends to destroy motion in a body.
It may be a pull or push that causes changes in motion in a body at rest and it adds acceleration or retardation to a body in motion.
The line along which it acts is called as line of action and the point at which it is applied to a body is called as point of application.
Force is a vector quantity. It has both magnitude and direction.
Representation:
A force vector is often represented graphically as an arrow:
The length of the arrow corresponds to the magnitude of the force.
The direction of the arrow indicates the direction of the force.
It is denoted by \( \mathbf{\vec{F}}\) =ma
where m= mass of the body and a= acceleration produced.
Characteristics of a force
The specifications or characteristics of a force are –
- Magnitude of the force .
- Direction along which force acts.
- The point of application.
- It’s nature(whether it is pull or push).
Effects of a force
A force may produce the following effects in a body, on which it acts :
- It may change the state of motion in the body. i.e. if a body is at rest, the force may put it in motion and if the body is already in motion, the force may accelerate or retard the motion.
- Force can change the direction of an object
- It may retard the effect of any force already acting on the body or normalize it or can bring it to equilibrium.
- It may induce a stress inside the body.
- It may cause deformation in the body.
Units of force
In C.G.S system Unit of force is gram cm/\(sec^2\) or it is known as Dyne
In S.I system Unit of force is Kg m/\(sec^2\) or it is known as Newton (N)
Dimension of Force:
Dimension of Force is ML\(T^{-2}\)