You need to understand first the definition of force as being that action that produces different kinds of changes over an object. The force concept only exists in presence of two objects at least.
The type of force is given by physical relative position of two or more objects, such that:
- contact forces (the objects physically interact)
- distance forces (the objects are not connected)
The group of contact forces contains the following sub-groups, such that: applied forces, normal forces, friction forces, spring forces, tension forces, air resistance.
The group of distance forces contains the following sub-groups, such that: electric forces, magnetic forces, gravitational forces.
There exists formulas to evaluate different kinds of forces, such that:
Newton's second law: `F = m*a` (F = force exerted on object, m = mass of object that suffers the action of force, a = acceleration of the object)
Friction force: `F_f = mu*F_n` (`F_n` = normal force)
Gravitational force: `G = m*g` (`g = 9.8 N/Kg` gravitational acceleration)
Force is basically represented by vectors also known as arrows that show direction and magnitude. It is defined as the movement or physical action that is the cause of change in the state of an object or cause a change in the shape and size of an object.
Force is divided unto two main categories:-
- Contact forces (The action that causes movement in an object due to physical contact)
- Non-contact forces (The action that causes movement in an object but not due to physical contact)
CONTACT FORCES ARE AS FOLLOWS:-
- Muscular (Force due to the action of muscles)
- Frictional (Force that tends to work in opposite direction when we move an object trying to stop it depending on the nature of the surface)
NON_CONTACT FORCES ARE AS FOLLOWS:-
- Gravitational (Force of gravity that tends to keep anything close to the surface of the earth)
- Electrostatic (Electric force between two charged objects)
- Magnetic (Force applied by magnet)