Introduction to Physics

• Physics is a natural science that studies matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force.
• Physics is one of the most fundamental scientific disciplines.
• Its goal is to understand how the universe behaves.

Core Concepts

• Physics covers a wide range of phenomena, from subatomic particles to galaxies.
• It's closely related to other sciences like mathematics, chemistry, and biology.
• Physics provides the fundamental principles that underpin these other sciences.

Classical Mechanics

• Deals with the motion of macroscopic objects.
• Key concepts include:
  • Newton's laws of motion: describe the relationship between force, mass, and acceleration.
  • Energy: the capacity to do work.
  • Momentum: a measure of mass in motion.
  • Conservation laws: energy, momentum, and angular momentum are conserved in closed systems.

Thermodynamics

• Studies heat, work, and energy transfer.
• Key concepts include:
  • Temperature: a measure of the average kinetic energy of particles in a system.
  • Heat: energy transferred due to a temperature difference.
  • Entropy: a measure of disorder in a system, which tends to increase.
  • Laws of thermodynamics: govern the flow of energy and the increase of entropy.

Electromagnetism

• Describes the interaction of electric charges and magnetic fields.
• Key concepts include:
  • Electric charge: a fundamental property of matter that causes it to experience a force in an electromagnetic field.
  • Electric field: a region of space around an electric charge that exerts a force on other charges.
  • Magnetic field: a region of space around a moving electric charge or a magnetic dipole that exerts a force on other moving charges.
  • Electromagnetic waves: oscillating electric and magnetic fields that propagate through space, including light.

Optics

• The study of light and its behaviour.
• Key concepts include:
  • Reflection: the bouncing of light off a surface.
  • Refraction: the bending of light as it passes from one medium to another.
  • Diffraction: the spreading of light waves as they pass through an opening or around an obstacle.
  • Interference: the superposition of light waves, resulting in constructive or destructive interference patterns.

Quantum Mechanics

• Deals with the behavior of matter at the atomic and subatomic levels.
• Key concepts include:
  • Quantization: energy, momentum, and other quantities are quantized, meaning they can only take on discrete values.
  • Wave-particle duality: particles can exhibit wave-like properties, and waves can exhibit particle-like properties.
  • Uncertainty principle: there is a fundamental limit to the precision with which certain pairs of physical properties of a particle, such as position and momentum, can be known simultaneously.
  • Quantum entanglement: two or more particles become linked together in a way that their fates are intertwined, regardless of the distance between them

Relativity

• Encompasses two related theories by Albert Einstein: special relativity and general relativity.
• Key concepts include:
  • Special relativity: describes the relationship between space and time, and the equivalence of mass and energy.
  • General relativity: describes gravity as a curvature of spacetime caused by mass and energy.
  • Time dilation: time passes slower for objects in stronger gravitational fields or moving at high speeds relative to an observe
  • Length contraction: the length of an object moving at high speeds appears to be shorter in the direction of motion.

Branches of Physics

• Astrophysics: applies physics to the study of celestial objects and phenomena.
• Biophysics: applies physics to the study of biological systems.
• Chemical physics: applies physics to the study of chemical systems.
• Geophysics: applies physics to the study of the Earth.
• Nuclear physics: studies the structure, behavior, and interactions of atomic nuclei.
• Particle physics: studies the fundamental constituents of matter and the forces that govern their interactions.
• Condensed matter physics: studies the physical properties of matter in its condensed phases (solid and liquid).