Mnemonics: Laws of Motion | Physics Class 11 - NEET PDF Download

1. Newton’s Three Laws of Motion

Types: First Law (Inertia), Second Law (Force = Mass × Acceleration), Third Law (Action-Reaction)

Mnemonic: "Ice Floats Around"

• Ice – First Law (Inertia)

• Floats – Second Law (Force = Mass × Acceleration)

• Around – Third Law (Action-Reaction)

First Law (Inertia): An object remains at rest or moves uniformly unless acted upon by an external force.

Second Law: The net force on an object is equal to the mass multiplied by its acceleration (F = ma).

Third Law: For every action, there is an equal and opposite reaction.

2. Types of Friction

Types: Static Friction, Kinetic Friction

Mnemonic: "Stop Kicking"

• Stop – Static Friction

• Kicking – Kinetic Friction

Static Friction resists the start of motion between two surfaces. It must be overcome to start movement.

Kinetic Friction acts between surfaces already in motion and is usually less than static friction.

3. Conditions for Equilibrium

Types: Net Force Zero, Net Torque Zero

Mnemonic: "No Tension"

• No – Net Force is Zero

• Tension – Net Torque is Zero

For an object to be in equilibrium:

• The net force acting on it must be zero to prevent any linear acceleration (translational equilibrium).

• The net torque must be zero to prevent any rotational acceleration (rotational equilibrium).

This ensures the object remains stationary or moves with constant velocity without rotating.