4.4 — Uniform circular motion
An object moving at constant speed along a circle — but at every instant, the direction of velocity changes. So it has acceleration! This is…
4.5 — Relative motion — inertial frames
Simple but deep question: “velocity” — with respect to whom? Every physical measurement happens in a “reference frame” — and the same event has…
4.6 — Worked problems — Chapter 4 toolkit in action
Seven worked problems tagged with the relevant §4.x section.
4.7 — Practice problems — 20 exercises for mastery
Twenty problems, three difficulty levels. Final answers at the end.
4.8 — Further reading and references
– Halliday, Resnick, Krane — Vol 1, Ch 4 – Halliday, Resnick, Walker — newer edition
4.9 — Q&A — Frequently asked questions for Chapter 4
1) Why are horizontal and vertical projectile motions independent?
Chapter 5 — Newton’s laws of motion
Newton’s three laws — inertia, F=ma, action-reaction — applied to weight, friction, pulleys, inclined planes, and connected systems.
5.1 — The concept of force and interaction
Force is an interaction between two objects that influences one of them. Vector quantity: magnitude and direction. SI unit: newton (N), equivalent to…
5.2 — Newton’s first law — inertia
If the net force is zero, an object continues in its state of motion — at rest or with constant velocity.
5.3 — Newton’s second law — F=ma
Net force on an object = mass × acceleration.