Force and Laws of Motion
Introduction
What is Force?
It is a push or pulls on an object that produces an acceleration in the body on which it acts. S.I. unit of force is Newton.
A force can do three things on a body.
• It can change the speed of the body.
• It can change the direction of motion of a body.
• It can change the shape of a body.
Balanced Forces – When equal amounts of forces are applied to an object from different directions such that they cancel out each other, such forces are known as balanced forces.
• Balanced forces do not change the state of rest or motion of an object.
• Balanced forces may change the shape and size of an object.
• If forces nullify one another then their resultant force is zero.
Unbalanced Force – When forces applied to an object are of different magnitude (or not in opposite directions to cancel out each other), such forces are unbalanced forces.
• Unbalanced forces can alter the state of rest or motion of an object.
• Unbalanced forces can cause acceleration in an object.
• Unbalanced forces can change the shape and size of an object.