1. PS2.A: Forces and Motions
1.1. Motion
1.1.1. Velocity
1.1.1.1. how fast something moves
1.1.2. Mass
1.1.2.1. Force that depends on gravity
1.1.3. Inertia
1.1.3.1. resistance of the object to any change in its motion
1.1.4. Momentum
1.1.4.1. quantity of motion of a moving object, measured as a product of its mass and velocity
1.2. Forces
1.2.1. Gravity
1.2.1.1. result of the curvature of spacetime caused by the uneven distribution of mass
1.2.2. Friction
1.2.2.1. resistance that a surface or object encounters when moving over another.
1.2.3. Magnetism
1.2.3.1. a physical occurrence produced by the motion of electric charge, resulting attractive and repulsive forces between objects
2. PS2.B Types of Interactions
2.1. Gravity
2.1.1. result of the curvature of spacetime caused by the uneven distribution of mass
2.2. Electromagnatism
2.2.1. Electric force
2.2.1.1. pushes all charged particles
2.2.2. magnetic force
2.2.2.1. pushes moving charges
2.3. Collisions
2.3.1. an instance of one moving object striking violently against another.
2.4. Strong and Weak Nuclear Interactions
2.4.1. change a neutron to a proton
2.4.1.1. Nuclear Decay
2.4.2. Strong Nuclear Force
2.4.2.1. positively charged protons and neutrally charged neurons
3. PS2.C: Stability and Instability in Physical Systems
3.1. Cyclical Patterns
3.1.1. Day and Night
3.2. Feedback Mechanisms
3.2.1. Maintain Stability
3.3. Changes
3.3.1. Quickly
3.3.2. Slowely
3.4. Balance
3.5. Imbalance
3.6. Stable Repearting Cycle
3.6.1. Prediction about systems future