3.0 FORCE

Force is a universal pillar of physics. In this chapter, we will explore its definition, effects, types, and associated laws in great detail. These notes are designed for learners who may not have access to textbooks, providing deep explanations and many practice questions.

3.1 Definition and Effects of Force

A force is a push or a pull that acts upon an object as a result of its interaction with another object. It is a vector quantity, meaning it has both magnitude (size) and direction. [citation:6]

Effects of a force: When a force is applied to an object, it can cause one or more of the following changes [citation:1]:

• Change in speed: It can make a stationary object move, or change the speed of a moving object (increase or decrease its velocity). For example, pushing a trolley accelerates it, while brakes decelerate a bicycle.
• Change in direction: It can make an object change its direction of motion. A footballer kicking a moving ball changes its direction; a magnet can change the direction of a moving iron nail.
• Change in shape (deformation): It can alter the shape or size of an object. Squeezing a sponge, stretching a rubber band, or pressing a clay lump all involve forces that change the object's shape. [citation:1]

3.2 Types of Forces

Forces are broadly classified into two main categories: contact forces and non-contact forces.

3.2.1 Contact Forces

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