Key Branches of Physics Overview

Classical Mechanics: Study of objects in motion, forces, and energy.
Thermodynamics: Study of heat, work, temperature, and energy transfer.
Electromagnetism: Study of electric charges, magnetic fields, and their interactions.
Optics: Study of light, its properties, and behavior.
Quantum Mechanics: Study of particles at atomic and subatomic levels.
Relativity: Study of the effects of gravity and the structure of space-time.

Force: A push or pull on an object, measured in Newtons (N).
Mass: Amount of matter in an object, measured in kilograms (kg).
Acceleration: Rate of change of velocity, measured in meters per second squared (m/s²).
Energy: The capacity to do work, exists in various forms (kinetic, potential, thermal, etc.).
Power: Rate of doing work or transferring energy, measured in Watts (W).

First Law (Inertia): An object at rest stays at rest, and an object in motion stays in motion unless acted upon by a net external force.
Second Law: Force equals mass times acceleration (F = ma).
Third Law: For every action, there is an equal and opposite reaction.

Conservation of Energy: Energy cannot be created or destroyed, only transformed.
Conservation of Momentum: In a closed system, the total momentum before and after an event remains constant.

Wave: Disturbance that transfers energy through a medium.
- Types: Transverse (e.g., light) and longitudinal (e.g., sound).
Frequency: Number of cycles per second, measured in Hertz (Hz).
Amplitude: Maximum displacement from rest position, related to wave energy.

Zeroth Law: If two systems are in thermal equilibrium with a third system, they are in equilibrium with each other.
First Law: Energy cannot be created or destroyed (conservation of energy).
Second Law: Entropy of an isolated system always increases; heat cannot spontaneously flow from cold to hot.
Third Law: As temperature approaches absolute zero, the entropy of a perfect crystal approaches zero.

Range of all types of electromagnetic radiation.
From low to high frequency: Radio waves, Microwaves, Infrared, Visible light, Ultraviolet, X-rays, Gamma rays.

Kinematics:
- ( v = u + at ) (velocity-time relation)
- ( s = ut + \frac{1}{2}at^2 ) (displacement)
Energy:
- Kinetic Energy ( KE = \frac{1}{2}mv^2 )
- Potential Energy ( PE = mgh )
Ohm’s Law: ( V = IR ) (Voltage = Current x Resistance)

Classical Mechanics focuses on motion, forces, and energy interactions of macroscopic objects.
Thermodynamics deals with heat, work, temperature changes, and energy flows between physical systems.
Electromagnetism investigates the behavior of electric charges and magnetic fields, affecting how they interact with each other.
Optics studies the nature and behavior of light, including its interactions with matter.
Quantum Mechanics explores the properties and behaviors of particles at atomic and subatomic scales.
Relativity examines the influence of gravity on time and space, established by Einstein's theories.

Force is quantified in Newtons (N), representing a push or pull acting on an object.
Mass measures the quantity of matter in an object, indicated in kilograms (kg).
Acceleration reflects the change in velocity over time, with units of meters per second squared (m/s²).
Energy is the ability to perform work, manifesting in various forms such as kinetic, potential, and thermal energy.
Power measures the rate of energy transfer or work done, expressed in Watts (W).

First Law (Inertia) states that objects will maintain their state of rest or uniform motion unless influenced by an external force.
Second Law defines the relationship between force, mass, and acceleration as ( F = ma ).
Third Law asserts that every action has an equal and opposite reaction, indicating mutual forces in interactions.

Conservation of Energy principle: Energy cannot be created or destroyed but can change forms.
Conservation of Momentum asserts that in an isolated system, total momentum remains unchanged before and after events.

A wave represents a disturbance that conveys energy through a medium.
Two main types of waves: Transverse (e.g., light), where displacement is perpendicular to wave direction, and longitudinal (e.g., sound), where displacement is parallel to wave direction.
Frequency measures the number of cycles occurring per second in Hertz (Hz).
Amplitude indicates the maximum distance from a resting position, correlating with energy level in the wave.

Zeroth Law: Systems in thermal equilibrium with a third system are in equilibrium with each other.
First Law reinforces energy conservation: energy cannot be created or destroyed.
Second Law relates to entropy, stating it always increases in isolated systems, and heat cannot naturally flow from cold to hot.
Third Law posits that as temperature nears absolute zero, a perfect crystal's entropy approaches zero.

The Electromagnetic Spectrum includes all forms of electromagnetic radiation, categorized from low to high frequency: Radio waves, Microwaves, Infrared, Visible light, Ultraviolet, X-rays, and Gamma rays.

Kinematics equations for motion:
- Velocity-time relationship: ( v = u + at )
- Displacement: ( s = ut + \frac{1}{2}at^2 )
Energy calculations:
- Kinetic Energy: ( KE = \frac{1}{2}mv^2 )
- Potential Energy: ( PE = mgh )
Ohm’s Law relates voltage, current, and resistance: ( V = IR ).

Engineering involves applying physical principles in mechanical, electrical, and civil engineering projects.
Medicine utilizes physics in fields like radiology and biophysics for diagnostics and treatment.
Environmental Science employs physics for climate modeling and advancing renewable energy solutions.
Technology relies on physics for developments in electronics and telecommunications, enhancing communication and innovation.