Scientific Concepts

Four forces that govern the universe:

Gravity is the attraction of all objects to all other objects. The more massive an object, the more attractive it is. Gravity has infinite range and is often described as a connective fabric, which is how to can act at a distance.

Electromagnetism is the attraction and repulsion of charged particles. It has infinite range and acts at the universe's speed limit. It is the singular phenomenon behind electricity, magnetism, and light. It is the second strongest force.

The Strong Interaction binds quarks to form protons and neutrons, and binds protons and neutrons to form the nucleus of atoms. It is the strongest force.

The Weak Interaction changes the flavor of quarks, allowing for radioactive decay and nuclear fusion of subatomic particles. It is the weakest force. 

Types of subatomic particles:

Electrons have a negative charge, very little mass, and no known substructure. They are the currency of physical interactions.

Protons have a positive charge, significant mass, and are made of three quarks. The count of protons in the nucleus is an element's atomic number. 

Neutrons have no charge, are more massive than protons, and are made of three quarks. They bind protons together in the nucleus, which would otherwise repel each other.

Electromechanical components of a circuit: 

Generator converts energy to electrons
Conductor passes electrons
Semiconductor filters electrons
Insulator inhibits electrons
Emitter converts electrons to signal
Sensor converts signal to electrons
Actuator converts electrons to energy



Electric properties of a circuit:
Voltage is the number of electrons
Resistance is the speed of electrons
Current is the density of electrons
Ohm's Law is V = I*R



Chemical processes in a circuit:
Electrode is the metallic contact to the non-metallic substance of an electric component

- Cathode: electrons flow into the cathode, electrical current flows out; site of reduction

- Anode: electrons flow out of the anode, electrical current flows into it; site of oxidation 

Redox is the portmanteau of chemical reactions occurring at the electrodes