Introduction to Physics and Mechanics

• Physics explores matter, energy, and the universe's fundamental forces.
• It aims to explain phenomena from subatomic particles to large-scale cosmological structures.
• Classical physics, developed primarily before the 20th century, includes mechanics, thermodynamics, optics, and electromagnetism.
• Modern physics encompasses quantum mechanics, relativity, and particle physics.

Mechanics

• Mechanics studies the motion of objects.
• It includes the forces that cause movement.
• Kinematics describes motion which disregards the causes.
• Dynamics focuses on how forces relate to motion, as described by Newton's laws.
• Newton's first law: objects at rest stay at rest; objects in motion stay in motion with the same velocity unless acted upon by a net force.
• Newton's second law: Net force equals mass times acceleration (F = ma).
• Newton's third law: Every action has an equal and opposite reaction.
• Work describes energy transferred by a force acting on an object.
• Energy exists as kinetic (motion) and potential (position).
• The law of conservation of energy states that energy can only change form.
• Momentum is an object's mass times velocity.
• The law of conservation of momentum states that a closed system's momentum remains constant without external forces.
• Rotational motion involves objects moving in circles.
• Torque is force's rotational equivalent.
• Angular momentum is the rotational equivalent of linear momentum.

Thermodynamics

• Thermodynamics studies heat, work, and energy transfer.
• Temperature measures the average kinetic energy of particles in a substance.
• Heat is energy transfer due to temperature differences.
• The laws of thermodynamics outlines how energy behaves in systems.
• The first law of thermodynamics states that energy is conserved.
• The second law of thermodynamics states that a closed system's entropy increases or stays constant.
• The third law of thermodynamics states that a system's entropy approaches a minimum as temperature nears absolute zero.
• Heat transfers through conduction, convection, and radiation.
• Conduction moves heat through a material due to temperature differences.
• Convection moves heat by the movement of fluids.
• Radiation transfers heat using electromagnetic waves.

Optics

• Optics concerns the behavior and properties of light.
• Reflection is light bouncing off a surface.
• Refraction is light bending as it passes through media.
• Lenses focus or diverge light.
• Mirrors reflect light.
• Wave optics describes light as a wave, explains interference and diffraction.
• Interference is wave superposition, resulting in constructive or destructive patterns.
• Diffraction is the bending of waves through openings or around obstacles.
• The electromagnetic spectrum consists of radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.

Electromagnetism

• Electromagnetism examines interactions between electric and magnetic fields.
• Electric charge is a fundamental property of matter.
• Electric force between charged objects relates to Coulomb's law.
• Electric field is force per unit charge at a point.
• Electric potential is potential energy per unit charge at a point.
• Electric current is the flow of charge.
• Resistance is opposition to electric current flow.
• Ohm's law states V = IR (voltage, current, resistance).
• Magnetism is the force of magnets on other magnets or moving charges.
• Magnetic field is the force per unit charge moving in a magnetic field.
• Electromagnetic induction is voltage production in a circuit due to a changing magnetic field.
• Maxwell's equations describes that electric and magnetic fields relate to each other

Quantum Mechanics

• Quantum mechanics explores matter's behavior at atomic and subatomic levels.
• Quantum mechanics predicts quantized energy, momentum, and physical quantities.
• Wave-particle duality shows particles acting as waves and particles.
• Heisenberg uncertainty principle: Position and momentum cannot both be perfectly known.
• Quantum entanglement links particles, sharing fate regardless of distance.

Relativity

• Relativity describes how space and time relate.
• Special relativity concerns space-time for constant velocity.
• General relativity relates space, time, and gravity.
• Einstein's E = mc² links energy and mass.
• Time dilation describes time slowing for moving objects.
• Length contraction describes length shortening for moving objects.
• Gravity is spacetime curvature from mass and energy.

Particle Physics

• Particle physics studies fundamental particles and forces.
• The Standard Model describes known particles/forces.
• Fundamental particles consist of quarks, leptons, and bosons.
• Quarks make up protons and neutrons.
• Leptons includes electrons and neutrinos.
• Bosons are force-carriers like photons (electromagnetic), gluons (strong), W/Z bosons (weak).
• The Higgs boson is responsible for mass.
• The four fundamental forces are gravity, electromagnetism, the strong nuclear force, and the weak nuclear force.

Overview of physics, the study of matter, energy, and fundamental forces. Classical physics includes mechanics, thermodynamics, and electromagnetism. Mechanics deals with motion and forces, including Newton's laws of motion.