Introduction to Physics: Core Concepts

• Physics is a natural science examining matter, its constituents, motion, behavior through space and time, and related entities like energy and force.
• The main goal of physics as a foundational scientific discipline is understanding the behavior of the universe.

Core Concepts

• Mechanics focuses on the motion of objects and the forces influencing their movement.
• Thermodynamics concerns heat and its relationship to various forms of energy.
• Electromagnetism studies interactions between electric currents/fields and magnetic fields.
• Optics explores the behavior and properties of light, including its interactions with matter.
• Quantum Mechanics investigates matter and energy behavior at atomic and subatomic levels.
• Relativity addresses the structure of spacetime and gravity.

Mechanics

• Kinematics describes motion focusing on displacement, velocity, and acceleration, without considering causes.
• Dynamics examines the causes of motion, linking force to changes in motion via Newton's laws.
• Newton's First Law: Objects at rest stay at rest, and objects in motion stay in motion with the same speed and direction unless acted upon by a force.
• Newton's Second Law: Force equals mass times acceleration (F = ma).
• Newton's Third Law: Every action has an equal and opposite reaction.
• Energy is the capacity to do work, measured in joules (J).
• Kinetic Energy is the energy of motion, calculated as 1/2 * mv^2 (m = mass, v = velocity).
• Potential Energy is stored energy, examples include gravitational (mgh) and elastic (1/2 * kx^2).
• Work represents energy transfer, calculated as force times distance (W = Fd).
• Power refers to the rate of work, measured in watts (W), with 1 W = 1 J/s.
• Momentum is the product of mass and velocity (p = mv).
• Conservation of Momentum: Total momentum in a closed system remains constant.
• Angular motion encompasses rotational kinematics and dynamics, including torque, angular momentum, and rotational energy.

Thermodynamics

• Temperature measures the average kinetic energy of particles in a substance, using Celsius (°C), Fahrenheit (°F), or Kelvin (K).
• Heat is energy transfer due to temperature differences, measured in joules (J).
• Zeroth Law of Thermodynamics: Systems in thermal equilibrium with a third system are in equilibrium with each other.
• First Law of Thermodynamics: Energy is conserved; the change in internal energy equals heat added minus work done (ΔU = Q - W.)
• Second Law of Thermodynamics: Entropy (disorder) in an isolated system increases or remains constant; heat doesn't spontaneously flow from cold to hot.
• Third Law of Thermodynamics: As temperature nears absolute zero, entropy approaches a minimum or zero.
• Heat Transfer occurs through conduction, convection, and radiation.
• Conduction involves heat transfer through a material without material movement.
• Convection involves heat transfer through fluid (liquids or gases) movement.
• Radiation involves heat transfer through electromagnetic waves.
• Heat Capacity is the heat needed to raise a substance's temperature by a certain amount.
• Specific Heat is the heat needed to raise the temperature of one unit mass of a substance by one degree.
• Phase Transitions, like melting, freezing, boiling, condensation, and sublimation, involve changes in the state of matter and are linked to latent heat.
• Latent Heat is the heat absorbed or released during a constant temperature phase change.

Electromagnetism

• Electric charge, measured in coulombs (C), is a fundamental property of matter.
• Coulomb's Law: F = k * (q1 * q2) / r^2 (k = Coulomb's constant, q1 & q2 = charges, r = distance).
• Electric field, measured in volts per meter (V/m), is the force per unit charge at a point in space.
• Electric potential, measured in volts (V), is electric potential energy per unit charge.
• Capacitance, measured in farads (F), is the ability to store electric charge.
• Current, measured in amperes (A), is the rate of electric charge flow.
• Resistance, measured in ohms (Ω), opposes electric current flow.
• Ohm's Law: V = IR (Voltage = Current x Resistance).
• Electric circuits involve electric current flow through interconnected components.
• Series circuits feature components along a single path.
• Parallel circuits feature components along multiple paths.
• Magnetism is the force exerted by magnets, attracting or repelling other magnets/magnetic materials.
• Magnetic Field, measured in teslas (T), surrounds magnets or current-carrying wires, exerting force on other magnets or moving charges.
• Electromagnetism describes interactions between electric currents/fields and magnetic fields.
• Faraday's Law of Induction: A changing magnetic field induces an electromotive force (EMF) in a circuit.
• Maxwell's Equations describe the behavior of electric and magnetic fields and their interactions.

Optics

• Light constitutes electromagnetic radiation visible to the human eye.
• Reflection involves light bouncing back from a surface.
• Refraction involves light bending as it moves between media.
• Snell's Law relates incidence and refraction angles to refractive indices of two media.
• Lenses refract light to create images.
• Convex lenses converge light rays.
• Concave lenses diverge light rays.
• Interference occurs when waves overlap, resulting in constructive (increased amplitude) or destructive (decreased amplitude) effects.
• Diffraction is the bending of waves passing through openings or around obstacles.
• Polarization aligns light wave oscillations in a specific direction.

Quantum Mechanics

• Quantum mechanics studies matter and energy at atomic and subatomic scales.
• Planck's constant (h) is a fundamental constant relating photon energy to its frequency.
• Wave-Particle Duality: Matter has both wave-like and particle-like characteristics.
• Uncertainty Principle: Precise simultaneous knowledge of a particle's position and momentum is impossible.
• Quantum Superposition: Particles exist in multiple states simultaneously until measured.
• Quantum Entanglement: Linked particles share the same fate regardless of distance.
• Quantum Tunneling: Particles can pass through potential barriers even without sufficient energy.
• Schrödinger Equation describes the time evolution of a physical system's quantum state.

Relativity

• Special Relativity addresses the relationship between space and time for observers at constant velocities.
• The speed of light in a vacuum is constant for all observers.
• Time Dilation: Time passes more slowly for moving observers.
• Length Contraction: Moving objects appear shorter.
• Mass-Energy Equivalence: Energy and mass are related by E = mc^2.
• General Relativity describes gravity as spacetime curvature due to mass and energy.
• Gravitational Lensing: Light bends around massive objects.
• Gravitational Waves: Accelerating masses cause ripples in spacetime.

An overview of physics, a natural science that studies matter, energy, and their interactions. Key areas include mechanics, thermodynamics, electromagnetism, optics, quantum mechanics and relativity. Includes introduction to Kinematics and Dynamics.