Physics Notes: Force

Based on the Cameroon GCE Ordinary Level Syllabus

Definition of Force

A force is a physical quantity that causes or tends to cause a change in the state of rest or motion of a body. It is a vector quantity, meaning it has both magnitude and direction.

SI Unit: Newton (N)

Types of Force

Contact Forces: Forces that arise from physical contact between objects.
- Frictional Force
- Tension Force
- Normal Force
- Air Resistance
Non-contact Forces: Forces that act at a distance.
- Gravitational Force
- Electrostatic Force
- Magnetic Force

Solving Problems Involving Force

Use Newton's Second Law: F = ma

Example 1:
A car of mass 1000 kg accelerates at 2 m/s². Find the force applied.
Solution:
F = ma = 1000 × 2 = 2000 N

Example 2:
A force of 10 N is applied to a 2 kg object. Find its acceleration.
Solution:
a = F/m = 10 / 2 = 5 m/s²

Applications of Force

Used in lifting and moving objects
Essential in transportation (cars, planes, trains)
Helps in construction and engineering (cranes, pulleys)
Used in sports to kick, throw, or hit objects
In machines to perform mechanical work