Key Concepts in Physics

Mechanics
- Study of motion and forces.
- Key laws: Newton's Laws of Motion.
  - First Law: An object at rest stays at rest; an object in motion stays in motion unless acted upon by a force.
  - Second Law: F = ma (Force equals mass times acceleration).
  - Third Law: For every action, there is an equal and opposite reaction.
Energy
- Types: Kinetic Energy (energy of motion) and Potential Energy (stored energy).
- Law of Conservation of Energy: Energy cannot be created or destroyed, only transformed from one form to another.
Waves and Oscillations
- Properties: Frequency, wavelength, amplitude, speed.
- Types: Mechanical waves (require a medium) and electromagnetic waves (do not require a medium).
- Sound waves: Longitudinal waves; characteristics include pitch and volume.
Thermodynamics
- Study of heat and energy transfer.
- Laws of Thermodynamics:
  - First Law: Energy cannot be created or destroyed; it can only change forms.
  - Second Law: Entropy of an isolated system always increases.
Electromagnetism
- Study of electric charges, currents, and magnetic fields.
- Key concepts:
  - Electric fields and potentials.
  - Ohm's Law: V = IR (Voltage equals current times resistance).
  - Maxwell's Equations: Describe how electric and magnetic fields interact.
Optics
- Study of light and its properties.
- Phenomena: Reflection, refraction, diffraction, and interference.
- Lens types: Convex (converging) and concave (diverging).
Modern Physics
- Focus on phenomena at atomic and subatomic levels.
- Quantum Mechanics: Describes behavior of particles and waves.
- Theory of Relativity: Introduces concepts of space-time, time dilation, and mass-energy equivalence (E=mc²).

Measurement and Units

SI Units: International System of Units.
- Length: meter (m)
- Mass: kilogram (kg)
- Time: second (s)
- Electric current: ampere (A)
- Temperature: kelvin (K)
- Amount of substance: mole (mol)

Key Principles and Formulas

Momentum: p = mv (momentum equals mass times velocity).
Work: W = Fd (work equals force times distance).
Power: P = W/t (power equals work done over time).
Free Fall: d = ½ gt² (distance fallen equals half of gravity times time squared).

Applications of Physics

Engineering: Principles used in design and construction.
Medicine: MRI, X-rays based on electromagnetic principles.
Environmental Science: Understanding energy transfers and conservation laws.

Important Scientists

Isaac Newton: Laws of motion and universal gravitation.
Albert Einstein: Theory of relativity and contributions to quantum mechanics.
Niels Bohr: Model of the atom and quantum theory advancements.

Mechanics

Study of motion and forces
Key laws: Newton's Laws of Motion
- First Law: An object at rest stays at rest; an object in motion stays in motion unless acted upon by a force
- Second Law: Force equals mass times acceleration (F = ma)
- Third Law: For every action, there is an equal and opposite reaction

Energy

Types:
- Kinetic Energy (energy of motion)
- Potential Energy (stored energy)
Law of Conservation of Energy states: Energy cannot be created or destroyed, only transformed from one form to another

Waves and Oscillations

Properties: Frequency, wavelength, amplitude, speed
Types:
- Mechanical waves (require a medium)
- electromagnetic waves (do not require a medium)
Sound waves are longitudinal waves
- Characteristics include pitch and volume

Thermodynamics

Study of heat and energy transfer
Laws of Thermodynamics:
- First Law: Energy cannot be created or destroyed; it can only change forms
- Second Law: Entropy of an isolated system always increases

Electromagnetism

Study of electric charges, currents, and magnetic fields
Key concepts:
- Electric fields and potentials
- Ohm's Law: Voltage equals current times resistance (V = IR)
- Maxwell's Equations: Describe how electric and magnetic fields interact

Optics

Study of light and its properties
Phenomena: Reflection, refraction, diffraction, and interference
Lens types:
- Convex (converging)
- Concave (diverging)

Modern Physics

Focus on phenomena at atomic and subatomic levels
Quantum Mechanics: Describes behavior of particles and waves
Theory of Relativity: Introduces concepts of space-time, time dilation, and mass-energy equivalence (E=mc²)

Measurement and Units

SI Units: International System of Units
- Length: meter (m)
- Mass: kilogram (kg)
- Time: second (s)
- Electric current: ampere (A)
- Temperature: kelvin (K)
- Amount of substance: mole (mol)

Key Principles and Formulas

Momentum: p = mv (momentum equals mass times velocity)
Work: W = Fd (work equals force times distance)
Power: P = W/t (power equals work done over time
Free Fall: d = ½ gt² (distance fallen equals half of gravity times time squared)