Waves & Optics
Wave Speed, Frequency and Wavelength
Three quantities describe every wave in the universe, and one tidy equation ties them together — master it and you…
Waves & Optics
Classical Mechanics
Gravitational Force and Newton’s Law of Gravitation
The same force that drops an apple holds the Moon in orbit, and Newton captured it all in one famous…
Thermodynamics
The First Law of Thermodynamics
The first law is energy bookkeeping for heat and work, proving that you can never get something for nothing in…
Classical Mechanics
Conservation of Momentum
When no outside force interferes, the total momentum of a system stays locked in place, which is why rockets fly…
Kinematics
Projectile Motion: The Complete Guide
A thrown ball obeys two simple, independent rules at once, and splitting its motion into horizontal and vertical parts turns…
Classical Mechanics
What Is Energy?
Energy is the universal currency that lets one thing change another, never created or destroyed but endlessly traded between motion,…
Classical Mechanics
Newton’s Second Law: F = ma
The most famous equation in mechanics ties force, mass, and acceleration into a single rule that predicts how every push…
Waves & Optics
Transverse Waves Explained
In a transverse wave the medium shakes sideways while the wave races forward, a simple sideways dance that explains light,…
Classical Mechanics
Newton’s Laws of Motion: All Three Laws Explained
Three short rules from 1687 still govern every car, rocket, and falling apple, turning the chaos of motion into a…