1.1 Inertia

1.1 Inertia
1.2 Momentum

2.1 Equations of Newton's second law of motion

4.1 Types of force

7.1 Pulley
7.2 Constrained motion

9.1 Angle of friction $\left( \lambda \right)$
9.2 Angle of repose $\left( \alpha \right)$

Any body cannot change its velocity by itself, without external force acting on it. This property is known as inertia.

When a car suddenly starts moving, the passenger in the car is thrown back due to inertia of rest. Similarly, when car stops suddenly, the passenger stoop forward due to inertia of motion.