Key Concepts in Physics

Gravitational Force:
- Weakest force; acts over long distances.
- Responsible for the attraction between masses.
Electromagnetic Force:
- Acts between charged particles.
- Responsible for electricity, magnetism, and light.
Weak Nuclear Force:
- Responsible for processes like beta decay in atoms.
- Operates at subatomic levels.
Strong Nuclear Force:
- Holds protons and neutrons together in atomic nuclei.
- Strongest force but acts over very short distances.

First Law (Inertia):
- An object at rest stays at rest and an object in motion stays in motion unless acted upon by a net external force.
Second Law (F=ma):
- The force acting on an object equals the mass of that object multiplied by its acceleration.
Third Law (Action-Reaction):
- For every action, there is an equal and opposite reaction.

Kinetic Energy (KE): Energy of motion, calculated as KE = 1/2 mv².
Potential Energy (PE): Stored energy due to position; gravitational PE = mgh.
Conservation of Energy: Energy cannot be created or destroyed, only transformed from one form to another.

Wave Properties:
- Wavelength, frequency, amplitude, and speed.
Types of Waves:
- Mechanical (require medium) and electromagnetic (do not require medium).
Sound Waves: Longitudinal waves that travel through compressions and rarefactions.
Light Waves: Transverse electromagnetic waves.

First Law: Energy cannot be created or destroyed; it can only change forms.
Second Law: Entropy of an isolated system always increases; heat flows from hot to cold.
Third Law: As temperature approaches absolute zero, the entropy of a system approaches a constant minimum.

Ohm’s Law: V = IR (Voltage = Current × Resistance).
Circuit Components: Resistors, capacitors, inductors, batteries.
Magnetic Fields: Produced by moving electric charges; follow the right-hand rule.

Special Relativity:
- Time and space are relative; speed of light is constant.
- Time dilation and length contraction.
General Relativity:
- Gravity is the curvature of spacetime caused by mass.

Wave-Particle Duality: Particles exhibit both wave and particle properties.
Uncertainty Principle: It is impossible to know both the position and momentum of a particle with absolute precision.

Nuclear Physics: Study of atomic nuclei, nuclear reactions (fission and fusion).
Particle Physics: Study of fundamental particles and their interactions (e.g., quarks, leptons).

Gravitational Force: The weakest force, but acts over incredibly long distances. Attracts objects based on their mass. This force is responsible for keeping planets in orbit and the formation of stars.
Electromagnetic Force: Responsible for everyday phenomena like electricity and magnetism, as well as light. Acts between charged particles. It is weaker than the strong force but much stronger than gravity.
Weak Nuclear Force: Works at the subatomic level, responsible for processes like beta decay in atoms. It is responsible for the radioactive decay of certain isotopes.
Strong Nuclear Force: The strongest force, but only operates over very short distances, binding protons and neutrons together in atomic nuclei. It is responsible for the stability of atomic nuclei.

First Law (Inertia): Objects at rest stay at rest, and objects in motion stay in motion at a constant velocity unless acted upon by an external force.
Second Law (F=ma): The force acting on an object is directly proportional to its mass and acceleration.
Third Law (Action-Reaction): For every action, there is an equal and opposite reaction.

Kinetic Energy (KE): The energy of motion. Calculated using the formula KE = 1/2 mv², where m is mass and v is velocity.
Potential Energy (PE): Stored energy due to an object's position or configuration. For gravitational PE, the formula is PE = mgh, where m is mass, g is gravitational acceleration, and h is height.
Conservation of Energy: Energy cannot be created or destroyed, only converted from one form to another.

Wave Properties: Key properties include wavelength (distance between two crests or troughs), frequency (number of waves passing a point per second), amplitude (height of the wave), and speed (how fast the wave travels).
Types of Waves:
- Mechanical waves require a medium to travel through (like sound waves in air) while electromagnetic waves can travel through a vacuum (like light waves).
Sound Waves: Longitudinal waves that travel through compressions (high pressure) and rarefactions (low pressure) of the medium.
Light Waves: Transverse electromagnetic waves, meaning they oscillate perpendicular to the direction of wave propagation.

First Law: Energy cannot be created or destroyed, only changed from one form to another.
Second Law: In an isolated system, entropy (a measure of disorder) will always increase. This means that heat will always naturally flow from a hot object to a colder object.
Third Law: As the temperature of a system approaches absolute zero (-273.15°C), the entropy of the system approaches a constant minimum.

Ohm's Law: Defines the relationship between voltage (V), current (I), and resistance (R) in an electrical circuit. V = IR, where V is the potential difference across a resistor, I is the current flowing through it, and R is the resistance.
Circuit Components: Common circuit components include resistors (oppose current flow), capacitors (store electrical energy), inductors (oppose changes in current), and batteries (provide a voltage difference).
Magnetic Fields: Produced by moving electric charges, these fields follow the right-hand rule (if the thumb points in the direction of current flow, the curled fingers point in the direction of the magnetic field lines).

Special Relativity: Proposes that time and space are relative concepts, and the speed of light is constant for all observers. This leads to concepts like time dilation (time slows down for objects moving at high speeds) and length contraction (objects appear shorter in the direction of motion at high speeds).
General Relativity: Explains gravity as the curvature of spacetime, caused by the presence of mass and energy.

Wave-Particle Duality: Particles, like photons or electrons, can exhibit both wave-like behavior (e.g., diffraction) and particle-like behavior (e.g., collisions).
Uncertainty Principle: It is impossible to know both the position and momentum of a particle with absolute certainty.

Nuclear Physics: Studies the structure and behavior of atomic nuclei, including nuclear reactions like fission (splitting of an atom) and fusion (combining of atoms).
Particle Physics: Explores the fundamental building blocks of matter, including quarks and leptons.

Engineering and Technology Development: Physics principles are fundamental to developing new technologies, from bridges and airplanes to computers and smartphones.
Medical Imaging: Medical technologies like MRI (magnetic resonance imaging), X-rays, and PET scans are based on physics principles.
Renewable Energy: Solar panels and wind turbines harness energy from the sun and wind, respectively, using principles of physics.
Electronics and Telecommunications: Our digital world is built on physics principles governing the behavior of electrons in semiconductors, leading to the development of computers, phones, and the internet.