Class 11 Physics Chapter 4 Laws of Motion – Revision Notes

Quick revision notes for Class 11 Physics Chapter 4 (Laws of Motion). These Class 11 Physics Chapter 4 notes are ideal for quick revision just before exams.

Newton’s Three Laws

• 1st Law: inertia; no motion change without net force.
• 2nd Law: F=dp/dt=ma.
• 3rd Law: action-reaction pairs, equal and opposite, on different bodies.

Momentum

• p=mv; conserved when no external force acts.

Friction

• Static: f_s(max)=μ_sN.
• Kinetic: f_k=μ_kN.

Circular Motion

• F=mv²/r; banked road ideal speed v=√(rg tanθ).

One-Line Summary

Newton’s three laws govern motion and force; momentum is conserved in isolated systems, and friction is a self-adjusting resistive force between contacting surfaces.

Written by Satish

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