Physics Classical Mechanics and Thermodynamics

Classical Mechanics

• Classical mechanics describes the motion of macroscopic objects, typically at everyday speeds.
• It utilizes Newton's laws of motion to predict and analyze motion.
• Key concepts include position, velocity, acceleration, force, mass, momentum, energy, and torque.
• Newton's first law (law of inertia): An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
• Newton's second law: The acceleration of an object is directly proportional to the net force acting on it and inversely proportional to its mass. (F = ma)
• Newton's third law: For every action, there is an equal and opposite reaction.
• Applications include analyzing projectile motion, circular motion, and simple harmonic motion.

Thermodynamics

• Thermodynamics deals with heat, energy, and work.
• Key concepts include temperature, heat, internal energy, entropy, and the laws of thermodynamics.
• Zeroth Law of Thermodynamics: If two thermodynamic systems are separately found to be in thermal equilibrium with a third, then they are in thermal equilibrium with each other.
• First Law of Thermodynamics: Energy can neither be created nor destroyed; it can only change forms. (ΔU = Q - W) where ΔU is the change in internal energy of a system, Q is the heat added to the system, and W is the work done by the system.
• Second Law of Thermodynamics: The total entropy of an isolated system can never decrease over time.
• Third Law of Thermodynamics: The entropy of a perfect crystal at absolute zero temperature (0 Kelvin) is zero.
• Applications include understanding engines, refrigerators, and heat transfer processes.

Electromagnetism

• Electromagnetism investigates the interplay between electric and magnetic phenomena.
• Key concepts include electric and magnetic fields, electric charge, current, voltage, and electromagnetic induction.
• Electric fields are generated by charges and exert forces on other charges.
• Magnetic fields are generated by moving charges and exert forces on other moving charges.
• Electromagnetic waves are produced by accelerating charges and exhibit wave-like properties.
• Faraday's Law: A changing magnetic field induces an electromotive force (EMF) and therefore a current in a conductor.
• Maxwell's equations describe the fundamental laws governing electromagnetism.
• Applications include electronics, telecommunications, and power generation.

Optics

• Optics focuses on the behavior and properties of light.
• Key concepts include reflection, refraction, diffraction, interference, and polarization.
• 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 as it passes through an aperture or around an obstacle.
• Interference: The superposition of light waves, resulting in either constructive or destructive interference.
• Polarization: The direction of the electric field vector in a light wave.
• Applications include lenses, telescopes, microscopes, and optical fibers.

Modern Physics

• Modern physics extends classical physics to the microscopic and relativistic realms.
• Key concepts include quantum mechanics, special relativity, and general relativity:
• Quantum mechanics describes the behavior of matter and energy at the atomic and subatomic levels.
• Special relativity deals with the relationships between space and time for objects moving at constant speeds, especially close to the speed of light.
• General relativity describes gravity as a curvature of spacetime caused by mass and energy.
• Applications include understanding atomic structure, particle physics, cosmology, and black holes.