Key Concepts in Physics

Matter: Anything that has mass and occupies space.
Energy: The ability to do work; exists in various forms (kinetic, potential, thermal).
Force: An interaction that changes the motion of an object; measured in Newtons (N).

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

Kinetic Energy (KE): Energy of motion; KE = 1/2 mv².
Potential Energy (PE): Energy stored due to position; gravitational PE = mgh.
Thermal Energy: Energy related to the temperature of an object.

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

Types of Waves:
- Mechanical waves (require a medium) and electromagnetic waves (do not require a medium).
Wave Properties:
- Wavelength, frequency, amplitude, speed.
Sound: A mechanical wave that travels through a medium; characterized by frequency and amplitude.

Laws of Thermodynamics:
1. Zeroth Law: If two systems are in thermal equilibrium with a third, they are in equilibrium with each other.
2. First Law: Energy cannot be created or destroyed; ΔU = Q - W (change in internal energy equals heat added minus work done).
3. Second Law: Entropy of an isolated system always increases; heat cannot spontaneously flow from cold to hot.
4. Third Law: As temperature approaches absolute zero, the entropy of a perfect crystal approaches zero.

Electric Charge: Positive and negative charges; like charges repel, opposite charges attract.
Ohm's Law: V = IR (Voltage equals current times resistance).
Magnetic Fields: Produced by moving charges; affect other moving charges and magnetic materials.

Relativity:
- Special Relativity: Time and space are relative; speed of light is constant.
- General Relativity: Gravity is the curvature of spacetime caused by mass.
Quantum Mechanics: Describes behavior of matter and energy at atomic and subatomic levels; incorporates principles like uncertainty and wave-particle duality.

Scientific Method: Observation, hypothesis, experimentation, conclusion.
Dimensional Analysis: Technique to convert units and check the consistency of equations.

Engineering: Application of physics principles to design and build structures, machines, and systems.
Technology: Innovations such as electronics, transportation, and energy production are grounded in physics concepts.

These notes provide a foundational overview of physics, highlighting essential concepts and principles crucial for further study in the subject.

Matter has mass and occupies space, forming the basis of physical existence.
Energy enables work to be done and exists in various forms: kinetic (motion), potential (position), and thermal (temperature-related).
Force, measured in Newtons (N), is an interaction that causes a change in an object's motion.

Newton's First Law states that a body at rest remains at rest, while a body in motion continues in motion unless acted upon by an external force.
Newton's Second Law is summarized by the equation F = ma, defining the relationship between force, mass, and acceleration.
Newton's Third Law asserts that every action has an equal and opposite reaction, highlighting the reciprocal nature of forces.

Kinetic Energy (KE) is defined as KE = 1/2 mv², where 'm' is mass and 'v' is velocity.
Potential Energy (PE) due to an object's position is represented by gravitational PE = mgh, where 'g' is the acceleration due to gravity and 'h' is height.
Thermal Energy refers to the energy associated with the temperature of an object.

Energy conservation illustrates that energy is neither created nor destroyed, only transformed from one form to another.
Momentum conservation indicates that the total momentum in a closed system remains constant before and after any event.

Waves are categorized into mechanical waves (require a medium) and electromagnetic waves (do not require a medium).
Wave properties include wavelength, frequency, amplitude, and speed; these determine the characteristics of sound, a type of mechanical wave.
Sound is characterized by both frequency (pitch) and amplitude (volume).

The Zeroth Law states that if two systems are in thermal equilibrium with a third system, they are in equilibrium with each other.
The First Law of Thermodynamics establishes that energy cannot be created or destroyed, expressed as ΔU = Q - W.
The Second Law posits that the entropy of an isolated system always increases, implying that heat cannot spontaneously flow from a colder to a hotter body.
The Third Law defines that as temperature approaches absolute zero, the entropy of a perfect crystal approaches zero.

Electric charges come in positive and negative forms, with like charges repelling each other and opposite charges attracting.
Ohm's Law is stated as V = IR, establishing the relationship between voltage (V), current (I), and resistance (R).
Magnetic fields arise from moving charges and influence other moving charges as well as magnetic materials.

Special Relativity posits that time and space are relative, with the speed of light being constant regardless of the observer's motion.
General Relativity describes gravity as the curvature of spacetime influenced by mass.
Quantum Mechanics examines the behavior of matter and energy at atomic and subatomic levels, featuring principles such as uncertainty and wave-particle duality.

The Scientific Method involves observation, forming a hypothesis, conducting experimentation, and drawing conclusions.
Dimensional Analysis is a method used to convert units and ensure the consistency of equations.

Engineering applies physics principles to design and construct structures, machines, and systems.
Technology relies on physics concepts to develop innovations in electronics, transportation, and energy production.