In science, a push or pull of an object is known as force. The interaction between two objects arises force. Force has both magnitude and direction. The strength of a force is expressed in magnitude. Force brings about a change in the direction or state of motion of a body. In Class 8 Science Chapter 11, various characteristics of force, along with the types of force are discussed.
A push is a force exerted away from the body, for example, Hitting a snooker ball, or kicking a football.
The force of attraction or repulsion between two magnetic bodies due to their poles is known as a magnetic force.
A pull is a force exerted towards the body, for example, drawing a bucket of water from a well or playing tug of war.
– Vector quantities are expressed in magnitude as well as the direction of the object. For example, velocity, displacement, weight, momentum, force, acceleration etc.
– Vectors are used to find the resultant component acting on a body.
– When multiple forces act on a body, they can be resolved into one component known as the net force acting on the object.
Example:
– A force is an effort that changes the state of an object at rest or in motion.
– It can change an object’s direction and velocity.
– Force can also change the shape of an object.
The state of motion of an object is defined by its velocity – the speed with a direction. Thus, inertia could be redefined as follows:
Inertia = tendency of an object to resist changes in its velocity.
An object at rest has zero velocity – and (in the absence of an unbalanced force) will remain with a zero velocity; it will not change its state of motion (i.e., velocity). An object in motion with a velocity of 2 m/s, East; will (in the absence of an unbalanced force) remain in motion with a velocity of 2 m/s, East; it will not change its state of motion (i.e., velocity). Objects resist changes in their velocity.