Key Concepts in Physics

Gravitational Force: Attraction between masses; governs planetary motion.
Electromagnetic Force: Interaction between charged particles; responsible for electricity and magnetism.
Strong Nuclear Force: Holds protons and neutrons together in the nucleus; strongest force over short ranges.
Weak Nuclear Force: Responsible for radioactive decay and neutrino interactions.

First Law (Inertia): An object at rest remains at rest, and an object in motion continues in motion unless acted upon by a net external force.
Second Law (F=ma): The force acting on an object is equal to the mass of the object multiplied by its acceleration.
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): Stored energy; gravitational PE = mgh.
Conservation of Energy: Energy cannot be created or destroyed, only transformed from one form to another.

First Law (Conservation of Energy): Energy in a closed system is conserved.
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.

Wave Properties: Wavelength, frequency, speed, amplitude.
Types of Waves:
- Mechanical: Require a medium (e.g., sound, water).
- Electromagnetic: Do not require a medium (e.g., light).
Superposition: When two or more waves overlap, their amplitudes add together.

Ohm's Law: V = IR (Voltage = Current × Resistance).
Magnetic Fields: Created by moving charges; direction given by the right-hand rule.
Electromagnetic Induction: Generation of an electromotive force (EMF) by changing the magnetic environment of a coil of wire.

Relativity: Einstein's theories explaining the relationships between space, time, and energy; introduces concepts of spacetime and mass-energy equivalence (E=mc²).
Quantum Mechanics: Study of phenomena at atomic and subatomic levels; wave-particle duality, uncertainty principle.

SI Units:
- Length (meter, m)
- Mass (kilogram, kg)
- Time (second, s)
- Electric Current (ampere, A)
- Temperature (kelvin, K)
- Amount of Substance (mole, mol)
- Luminous Intensity (candela, cd)

Gravitational Force: Attracts objects with mass, governs planetary motion and the formation of galaxies.
Electromagnetic Force: Acts on charged particles, responsible for electricity, magnetism, and light.
Strong Nuclear Force: Holds protons and neutrons together in the nucleus; strongest force but only operates over very short distances.
Weak Nuclear Force: Responsible for radioactive decay and neutrino interactions.

First Law (Inertia): An object at rest stays at rest, and an object in motion stays in motion at a constant speed and direction unless acted upon by an unbalanced external force.
Second Law (F=ma): The force acting on an object is directly proportional to the mass and acceleration of the object.
Third Law: For every action, there is an equal and opposite reaction.

Kinetic Energy: Energy of motion, calculated using KE=1/2mv².
Potential Energy: Stored energy based on an object's position or state; gravitational potential energy is calculated using PE=mgh.
Conservation of Energy: A fundamental principle stating that energy cannot be created or destroyed, only transformed from one form to another. This principle is key for understanding energy transfers in many systems.

First Law (Conservation of Energy): Energy in a closed system remains constant; it is not created or destroyed but can be converted into different forms.
Second Law: Entropy, a measure of disorder, always increases in an isolated system. This means heat spontaneously flows from hotter objects to colder objects.
Third Law: As the temperature of a system approaches absolute zero, the entropy of a perfect crystal approaches zero.

Wave Properties:
- Wavelength: Distance between successive crests or troughs in a wave.
- Frequency: Number of waves passing a point in a given amount of time.
- Speed: How fast the wave travels.
- Amplitude: The maximum displacement of a wave from its equilibrium position.
Types of Waves:
Mechanical: Require a medium to travel (e.g., sound waves in air, water waves).
Electromagnetic: Do not require a medium to travel (e.g., light, radio waves).
Superposition: When two or more waves overlap, their amplitudes add together (constructive interference) or cancel each other out (destructive interference).

Ohm's Law: Relates voltage, current, and resistance in a circuit.
Magnetic Fields: Created by moving charges; the direction of the magnetic field is determined by the right-hand rule.
Electromagnetic Induction: The process of generating an electromotive force (EMF) in a coil of wire by changing the magnetic environment around the coil.

Relativity: Einstein's theories of special and general relativity, which explain the relationships between space, time, gravity, and energy. Key concepts include:
- Spacetime: A four-dimensional continuum that combines space and time.
- Mass-Energy Equivalence (E=mc²): Describes the relationship between mass and energy, stating that they are interchangeable.
Quantum Mechanics: The study of physical phenomena at the atomic and subatomic levels. Key concepts include:
- Wave-Particle Duality: Particles can exhibit wave-like behavior and vice versa.
- Uncertainty Principle: It is impossible to simultaneously know both the position and momentum of a particle with perfect accuracy.

Dimensional Analysis: Use units to check the consistency of equations and formulas.
Free Body Diagrams: Visual representations of all forces acting on an object, which can help with solving dynamics problems.
Energy Methods: Use the principles of conservation of energy to solve dynamics problems, often simplifying calculations.

SI Units: The International System of Units, used globally in science and engineering.
- Length: meter (m)
- Mass: kilogram (kg)
- Time: second (s)
- Electric Current: ampere (A)
- Temperature: kelvin (K)
- Amount of Substance: mole (mol)
- Luminous Intensity: candela (cd)