Physics: Kinematics and Dynamics

Key concepts:
- Zeroth law: if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other
- First law (energy conservation): energy cannot be created or destroyed, only converted
- Second law: total entropy of an isolated system always increases over time
- Third law: as temperature approaches absolute zero, entropy approaches a minimum value

Key concepts:
- Isolated systems: no energy or matter exchanged with surroundings
- Closed systems: energy exchanged, but no matter exchanged
- Open systems: energy and matter exchanged with surroundings
- Thermodynamic equilibrium: state of balance among system and surroundings

Displacement is the shortest distance between initial and final positions
Velocity is the rate of change of displacement, measured in meters per second (m/s)
Acceleration is the rate of change of velocity, measured in meters per second squared (m/s²)
Time is a scalar quantity measuring duration, and is a fundamental concept in kinematics
Frames of reference can be inertial (at rest or moving at a constant velocity) or non-inertial (accelerating)

Force is a push or pull that causes motion, measured in Newtons (N)
Newton's first law states that objects at rest stay at rest, and objects in motion stay in motion, unless acted upon by an external force
Newton's second law states that force equals mass times acceleration (F = ma), and is a fundamental concept in dynamics
Newton's third law states that every action has an equal and opposite reaction
Energy has two main forms: kinetic energy (the energy of motion) and potential energy (the energy of position or configuration)
Momentum is the product of mass and velocity, and is a measure of an object's tendency to keep moving

Angular displacement is the angle of rotation, measured in radians (rad)
Angular velocity is the rate of change of angular displacement, measured in radians per second (rad/s)
Angular acceleration is the rate of change of angular velocity, measured in radians per second squared (rad/s²)
Torque is a rotational force, measured in Newton-meters (N·m)
Rotational kinematics has analogs of linear kinematics, including angular displacement, angular velocity, and angular acceleration

The zeroth law states that if two systems are in thermal equilibrium with a third, they are in thermal equilibrium with each other
The first law states that energy cannot be created or destroyed, only converted from one form to another
The second law states that the total entropy of an isolated system always increases over time
The third law states that as temperature approaches absolute zero, entropy approaches a minimum value

Isolated systems exchange neither energy nor matter with their surroundings
Closed systems exchange energy, but not matter, with their surroundings
Open systems exchange both energy and matter with their surroundings
Thermodynamic equilibrium is a state of balance among the system and its surroundings

Time dilation occurs when time appears to pass slower for moving observers
Length contraction occurs when objects appear shorter to moving observers
Relativity of simultaneity states that events simultaneous for one observer may not be for another
The speed of light is always constant, regardless of observer motion
The Lorentz transformation is a mathematical framework for special relativity

Gravitational time dilation occurs when time passes slower near massive objects
Gravitational redshift occurs when light emitted from massive objects appears redder
The equivalence principle states that gravity and acceleration are equivalent
Geodesics are the shortest paths in curved spacetime
Einstein's field equations provide a mathematical description of gravity and spacetime curvature