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Physics

Matter, energy, and the fundamental forces of the universe.

Motion & Forces

Motion & Forces is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Energy & Work

Energy & Work is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Waves & Sound

Waves & Sound is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Light & Optics

Light & Optics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Electricity & Magnetism

Electricity & Magnetism is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Thermodynamics

Thermodynamics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Modern Physics (Intro)

Modern Physics (Intro) is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Circular Motion & Gravitation

Circular Motion & Gravitation is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Momentum & Impulse

Momentum & Impulse is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Simple Harmonic Motion

Simple Harmonic Motion is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Fluid Mechanics (Intro)

Fluid Mechanics (Intro) is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Design principles, analysis methods, standards and codes, and real-world case studies.

Heat & Temperature

Heat & Temperature is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Kinetic Theory

Kinetic Theory is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Electromagnetic Induction

Electromagnetic Induction is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Circuits

Circuits is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Design principles, analysis methods, standards and codes, and real-world case studies.

Atomic Structure

Atomic Structure is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Nuclear Physics (Intro)

Nuclear Physics (Intro) is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Relativity (Intro)

Relativity (Intro) is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Quantum Physics (Intro)

Quantum Physics (Intro) is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Astronomy Basics

Astronomy Basics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Units & Measurement

Units & Measurement is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Vectors & Scalars

Vectors & Scalars is a core mathematics topic covering definitions, formulas, and problem-solving techniques essential for mastery.

Key points: Formal definition, derivation, worked examples, and common applications with step-by-step solutions.

Projectile Motion

Projectile Motion is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Friction

Friction is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Pressure & Buoyancy

Pressure & Buoyancy is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Classical Mechanics

Classical Mechanics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Design principles, analysis methods, standards and codes, and real-world case studies.

Electromagnetism

Electromagnetism is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Quantum Mechanics

Quantum Mechanics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Design principles, analysis methods, standards and codes, and real-world case studies.

Thermodynamics & Statistical Mechanics

Thermodynamics & Statistical Mechanics is a core mathematics topic covering definitions, formulas, and problem-solving techniques essential for mastery.

Key points: Design principles, analysis methods, standards and codes, and real-world case studies.

Optics & Photonics

Optics & Photonics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Nuclear Physics

Nuclear Physics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Particle Physics

Particle Physics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Astrophysics & Cosmology

Astrophysics & Cosmology is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Condensed Matter Physics

Condensed Matter Physics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Fluid Dynamics

Fluid Dynamics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Plasma Physics

Plasma Physics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

General Relativity

General Relativity is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Quantum Field Theory

Quantum Field Theory is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

String Theory

String Theory is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Computational Physics

Computational Physics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Biophysics

Biophysics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Geophysics

Geophysics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Acoustics

Acoustics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Solid State Physics

Solid State Physics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Atomic & Molecular Physics

Atomic & Molecular Physics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Optoelectronics

Optoelectronics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Nanophysics

Nanophysics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Chaos Theory

Chaos Theory is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Mathematical Physics

Mathematical Physics is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Experimental Methods

Experimental Methods is a fundamental physics concept explaining the behavior of matter and energy, with formulas and real-world applications.

Key points: Core principles, practical applications, and advanced concepts that build deep understanding.

Key Formulas & Equations

Newton's Second Law: F = ma
Newton's Law of Gravitation: F = G(m₁m₂)/r²
Kinematic Equation (no time): v² = v₀² + 2aΔx
Kinematic Equation (position): Δx = v₀t + (1/2)at²
Kinetic Energy: KE = (1/2)mv²
Gravitational Potential Energy: PE = mgh
Work: W = Fd·cos(θ)
Power: P = W/t = F·v
Momentum: p = mv
Impulse: J = FΔt = Δp
Hooke's Law: F = -kx
Ohm's Law: V = IR
Coulomb's Law: F = k(q₁q₂)/r²
Einstein's Mass-Energy: E = mc²
Photoelectric Effect: E = hf - φ
Ideal Gas Law: PV = nRT
First Law of Thermodynamics: ΔU = Q - W
Wave Speed: v = fλ

Core Concepts

Force

A push or pull on an object resulting from its interaction with another object. Measured in Newtons (N). Forces cause objects to accelerate, decelerate, change direction, or deform.

Energy

The capacity to do work. It exists in many forms: kinetic (motion), potential (stored), thermal, chemical, nuclear, and electrical. Energy is conserved — it cannot be created or destroyed, only transformed.

Momentum

A vector quantity defined as the product of an object's mass and velocity (p = mv). In a closed system, total momentum is conserved before and after collisions.

Wave-Particle Duality

Quantum objects exhibit both wave-like and particle-like behavior. Light behaves as a wave (interference, diffraction) and as particles (photons in the photoelectric effect). Matter also has wave properties (de Broglie wavelength).

Thermodynamics

The study of heat, temperature, and energy transfer. The Four Laws: (0) Thermal equilibrium is transitive; (1) Energy is conserved; (2) Entropy of an isolated system never decreases; (3) Absolute zero is unattainable.

Electromagnetic Induction

A changing magnetic field induces an electromotive force (EMF) in a conductor. Discovered by Faraday: ε = -dΦ_B/dt. This principle underlies generators, transformers, and wireless charging.

Worked Examples

Example 1: Projectile Motion

Problem: A ball is thrown horizontally at 10 m/s from a 45 m cliff. How far does it land from the base?

Step 1: Find time to fall: h = (1/2)gt² → 45 = (1/2)(9.8)t²

Step 2: t² = 90/9.8 = 9.18 → t = 3.03 s

Step 3: Horizontal distance: x = v₀t = 10 × 3.03 = 30.3 m

Answer: The ball lands approximately 30.3 meters from the base.

Example 2: Newton's Second Law

Problem: A 5 kg object accelerates at 3 m/s². What net force acts on it?

Step 1: Apply F = ma

Step 2: F = (5 kg)(3 m/s²) = 15 N

Answer: The net force is 15 Newtons.

Example 3: Circuit Analysis

Problem: A 12 V battery is connected to a 4 Ω resistor. Find the current.

Step 1: Apply Ohm's Law: V = IR

Step 2: Solve for I: I = V/R = 12/4 = 3 A

Answer: The current is 3 Amperes.

Example 4: Gravitational Potential Energy

Problem: How much PE does a 2 kg book gain when lifted 3 m?

Step 1: PE = mgh = (2)(9.8)(3)

Step 2: PE = 58.8 J

Answer: The book gains 58.8 Joules of potential energy.

Practice Problems

Problem 1

A car accelerates from 0 to 20 m/s in 5 s. What is its acceleration?

Answer: a = Δv/Δt = 20/5 = 4 m/s²

Problem 2

What is the kinetic energy of a 0.5 kg ball moving at 10 m/s?

Answer: KE = (1/2)(0.5)(10)² = 25 J

Problem 3

Two charges of 2 μC and 3 μC are 0.5 m apart. Find the electrostatic force. (k = 9×10⁹ N·m²/C²)

Answer: F = k(q₁q₂)/r² = (9×10⁹)(2×10⁻⁶)(3×10⁻⁶)/(0.5)² = 0.216 N

Problem 4

A wave has frequency 50 Hz and wavelength 2 m. What is its speed?

Answer: v = fλ = 50 × 2 = 100 m/s

Problem 5

How much work is done pushing a box 5 m with a force of 20 N at 0° angle?

Answer: W = Fd·cos(0°) = 20 × 5 × 1 = 100 J

Problem 6

A 60 kg person stands on a scale in an elevator accelerating upward at 2 m/s². What does it read?

Answer: N = m(g+a) = 60(9.8+2) = 60 × 11.8 = 708 N

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