Key Concepts in Physics

Kinematics: Study of motion without considering forces.
- Displacement, velocity, acceleration.
Dynamics: Study of forces and their effects on motion.
- Newton's Laws of Motion:
  1. An object at rest stays at rest; an object in motion stays in motion unless acted upon by a force.
  2. F = ma (Force equals mass times acceleration).
  3. For every action, there is an equal and opposite reaction.
Energy: The ability to do work.
- Kinetic Energy: ( KE = \frac{1}{2} mv^2 )
- Potential Energy: ( PE = mgh )
Momentum: ( p = mv ); conserved in isolated systems.

Laws of Thermodynamics:
- 1st Law: Energy cannot be created or destroyed, only transformed.
- 2nd Law: Entropy of an isolated system always increases.
- 3rd Law: As temperature approaches absolute zero, the entropy of a perfect crystal approaches zero.
Heat Transfer: Conduction, convection, and radiation.

Wave Properties: Wavelength, frequency, amplitude, speed.
Types of Waves:
- Mechanical (require medium): sound waves, water waves.
- Electromagnetic (do not require medium): light waves, radio waves.
Superposition Principle: Overlapping waves combine to form a resultant wave.

Electric Charge: Positive and negative; like charges repel, opposite charges attract.
Ohm's Law: ( V = IR ) (Voltage = Current x Resistance).
Magnetic Fields: Produced by moving charges; described by the right-hand rule.
Electromagnetic Induction: Changing magnetic fields can induce electric currents.

Quantum Mechanics: Study of particles at atomic and subatomic levels.
- Wave-particle duality, uncertainty principle, quantization of energy.
Relativity: Einstein's theories of special and general relativity.
- Special Relativity: Time dilation, length contraction, ( E = mc^2 ).
- General Relativity: Gravity as curvature of spacetime.

Structure of the Atom: Nucleus (protons and neutrons) surrounded by electrons.
Radioactivity: Emission of particles from unstable nuclei.
- Types: Alpha, beta, gamma decay.
Nuclear Fission/Fusion: Splitting/combing of nuclei releasing large amounts of energy.

Laws of Planetary Motion: Kepler's laws describe orbits of planets.
Cosmology: Study of the universe's origin, evolution, and fate.
Black Holes and Dark Matter: Concepts in understanding gravitational forces and universe structure.

SI Units:
- Length: meter (m)
- Mass: kilogram (kg)
- Time: second (s)
- Force: newton (N)
- Energy: joule (J)
- Power: watt (W)

Vectors and Scalars: Vectors have magnitude and direction; scalars have only magnitude.
Calculus: Used for analyzing change, especially in motion and growth.
Trigonometry: Essential for solving problems involving angles and distances in physics.

Kinematics: Analyzes motion properties like displacement, velocity, and acceleration without force consideration.
Dynamics: Examines forces and their implications on motion; governed by Newton's Laws of Motion:
- An object remains at rest or in uniform motion unless acted on by a net force.
- Force can be calculated as ( F = ma ) (mass times acceleration).
- Every action has an equal and opposite reaction.
Energy Types:
- Kinetic Energy: Given by ( KE = \frac{1}{2} mv^2 ).
- Potential Energy: Expressed as ( PE = mgh ) (mass times gravitational acceleration times height).
Momentum: Defined as ( p = mv ) (mass times velocity) and is conserved in closed systems.

Laws of Thermodynamics:
- First Law: Energy conservation; transformation is possible, not creation or destruction.
- Second Law: Increases in entropy signal energy dispersal; entropy in an isolated system cannot decrease.
- Third Law: Entropy of a perfect crystal approaches zero as temperature nears absolute zero.
Heat Transfer Mechanisms: Conduction (direct contact), convection (fluid movement), and radiation (electromagnetic waves).

Wave Characteristics: Include wavelength (distance between peaks), frequency (number of waves per time), amplitude (height), and speed (propagation rate).
Wave Types:
- Mechanical: Require a medium (e.g., sound and water waves).
- Electromagnetic: Do not require a medium (e.g., light and radio waves).
Superposition Principle: When waves overlap, they combine to create a resultant wave.

Electric Charge: Two types exist; like charges repel while opposite charges attract.
Ohm's Law: Connects voltage (V), current (I), and resistance (R) as ( V = IR ).
Magnetic Fields: Created by moving electric charges, determined by the right-hand rule.
Electromagnetic Induction: A process where changing magnetic fields generate electric currents.

Quantum Mechanics: Investigates atomic and subatomic particle behavior, featuring wave-particle duality and the uncertainty principle.
Relativity: Includes Einstein’s theories:
- Special Relativity: Deals with high-speed motion leading to time dilation and length contraction, represented by ( E = mc^2 ).
- General Relativity: Describes gravity as the curvature of spacetime caused by mass.

Atom Composition: Nucleus contains protons and neutrons, with electrons orbiting around it.
Radioactivity: Involves unstable nuclei emitting particles; types include alpha, beta, and gamma decay.
Nuclear Processes:
- Fission: Splitting large atomic nuclei releases energy.
- Fusion: Combining smaller nuclei also releases significant energy.

Kepler’s Laws: Describe planetary motion and orbits.
Cosmology: Explores the universe's beginnings, development, and ultimate fate.
Black Holes and Dark Matter: Essential concepts for understanding gravity and cosmic structure.

SI Units:
- Length: meter (m)
- Mass: kilogram (kg)
- Time: second (s)
- Force: newton (N)
- Energy: joule (J)
- Power: watt (W)

Vectors vs. Scalars: Vectors contain both magnitude and direction; scalars possess only magnitude.
Calculus: Fundamental for understanding change in relation to motion and rates of growth.
Trigonometry: Key for solving physics problems involving angles and spatial relationships.