Key Concepts in Physics

Motion: Change in position over time.
Velocity: Speed with direction.
Acceleration: Rate of change of velocity.
Equations of Motion:
- ( v = u + at )
- ( s = ut + \frac{1}{2}at^2 )
- ( v^2 = u^2 + 2as )

Newton's Laws of Motion:
1. An object at rest stays at rest; an object in motion stays in motion unless acted on by a force.
2. ( F = ma ) (Force equals mass times acceleration).
3. For every action, there is an equal and opposite reaction.

Kinetic Energy: ( KE = \frac{1}{2}mv^2 )
Potential Energy: ( PE = mgh ) (gravitational).
Conservation of Energy: Energy cannot be created or destroyed, only transformed.

Definition: Momentum ( p = mv ).
Conservation of Momentum: Total momentum before an event equals total momentum after.

Laws of Thermodynamics:
1. Energy is conserved in an isolated system.
2. Entropy of an isolated system always increases.
3. Absolute zero cannot be reached.
Heat Transfer: Conduction, convection, and radiation.

Wave Properties: Wavelength, frequency, amplitude, speed.
Types of Waves: Mechanical (require medium) and Electromagnetic (do not require medium).
Sound Waves: Longitudinal waves, characterized by compression and rarefaction.

Quantum Mechanics: Study of particles at atomic and subatomic levels.
Relativity: Einstein's Theory (Special and General) changing how we understand space and time.
Atomic Structure: Protons, neutrons, electrons; atomic models (Bohr, quantum mechanical).

Engineering: Application of physical principles to design structures and systems.
Technology: Development of devices based on physics (e.g., electronics, optics).
Astrophysics: Study of celestial bodies and the universe.

Gravitational Force: Attraction between masses, responsible for the orbits of planets and the structure of galaxies.
Electromagnetic Force: Interaction between charged particles, governs electricity, magnetism, and the behavior of atoms.
Strong Nuclear Force: Binds protons and neutrons within atomic nuclei, overcoming electromagnetic repulsion between positively charged protons.
Weak Nuclear Force: Mediates processes like beta decay in radioactive elements, plays a crucial role in nuclear reactions.

Motion is defined as the change in position of an object over time, can be analyzed through equations of motion.
Velocity is a vector quantity combining speed and direction, crucial for understanding movement dynamics.
Acceleration indicates the rate of change of velocity, measuring how quickly an object speeds up or slows down.
Key equations of motion:
- Final velocity ( v = u + at )
- Displacement ( s = ut + \frac{1}{2}at^2 )
- Velocity squared ( v^2 = u^2 + 2as )

Newton's Laws of Motion describe the relationship between forces and motion:
- First Law: An object remains at rest or in uniform motion until acted upon by an external force.
- Second Law: Force ( F = ma ); the acceleration of an object is proportional to the net force acting on it and inversely proportional to its mass.
- Third Law: For every action, there is an equal and opposite reaction, illustrating the mutual interactions between objects.

Kinetic Energy quantifies the energy of motion, expressed as ( KE = \frac{1}{2}mv^2 ).
Potential Energy represents stored energy, particularly gravitational potential energy ( PE = mgh ), where ( h ) is height.
Conservation of Energy states that energy in a closed system can neither be created nor destroyed, only transformed from one form to another.

Momentum is defined as the product of an object’s mass and velocity ( p = mv ), highlighting the relationship between motion and mass.
Conservation of Momentum asserts that the total momentum in a closed system remains constant before and after a collision or event.

Laws of Thermodynamics establish foundational principles:
- First Law: Energy conservation in isolated systems, energy can change forms but not be created or destroyed.
- Second Law: Entropy in an isolated system tends to increase over time, indicating the natural tendency towards disorder.
- Third Law: Absolute zero, the point at which molecular motion ceases, is unattainable.
Heat Transfer Methods: Conduction (direct contact), convection (fluid movement), and radiation (electromagnetic waves).

Wave Properties include wavelength, frequency, amplitude, and wave speed, essential for characterizing wave behavior.
Types of Waves:
- Mechanical Waves require a medium (e.g., sound).
- Electromagnetic Waves can travel through a vacuum (e.g., light).
Sound Waves are longitudinal waves characterized by areas of compression and rarefaction.

Electric Charge exists in two types: positive and negative, leading to the fundamental concept of electric forces.
Ohm's Law relates voltage, current, and resistance through the formula ( V = IR ), central to electrical circuits.
Magnetic Fields originate from moving charges, with the right-hand rule used to determine the direction of the field lines.

Quantum Mechanics deals with the behavior of particles at atomic and subatomic levels, introducing concepts like wave-particle duality.
Relativity, proposed by Einstein, revolutionized the understanding of time and space, introducing concepts of spacetime.
Atomic Structure comprises protons, neutrons, and electrons, with atomic models evolving from Bohr's model to modern quantum mechanics.

Engineering utilizes physics principles to design and analyze structures, machines, and systems effectively.
Technology relies on physics to create devices like electronics and optics, impacting everyday life.
Astrophysics focuses on the study of celestial bodies and the universe, merging physics with astronomical observations.

Prioritize understanding conceptual frameworks over rote memorization.
Regularly solve practice problems to apply theoretical knowledge.
Utilize diagrams for better visualization of concepts, particularly in mechanics.
Periodically review key formulas and principles to enhance retention.