(N/A) Force is required to bring a body at rest into motion or to stop a moving body. It is not always necessary to be in physical contact with the body. Hence,there are mainly two types of forces:
$(i)$ Contact Force:
In contact force,there is a physical interaction between objects. Due to contact with another body,the state of motion or rest of an object can be changed.
Contact force acts on both objects in contact.
Contact force can be a push or a pull.
Example: $A$ block lying on a table can be pushed or pulled. Here,the contact force acts on both the block and the table.
$(ii)$ Field Force (Non-contact Force):
When an object is in a gravitational field,magnetic field,or electric field,it experiences a force due to the field.
In field force,there is no physical interaction between objects.
Magnetic force,electric force,or gravitational force are examples of field forces.
Example $1$: An object falling freely from the top of a building has accelerated motion due to the gravitational field of the Earth. Here,there is no physical contact between the Earth and the object,yet it has accelerated motion.
Example $2$: When a nail is placed near a bar magnet,it is attracted due to the magnetic field of the bar magnet.