Circuit Lab

To see the old circuit lab page please refer to here.

Introduction
Continuing with my trend of the two previous help threads, (which will be linked at the bottom for anyone interested) I've decided to write a new shocking guide. A guide to that energizing event, Circuit Lab. If you were at all like me when you got these rules, you might've said "wtf mate?" But fear not, my fellow shocked-in-the-fingers-friends, for I've prepared a few notes, definitions, and various helpful items that hopefully won't short circuit (I'll explain that later) your brain.

What is a Circuit?
Let's take an example of a battery, for now. The battery has a positive (+) end, and a minus ( - ) end. When you touch a wire onto both ends of the battery at the same time, you have created a circuit. What just happened? Current flowed from one end of the battery to the other through your wire. Therefore, our definition of circuit can simply be a never-ending looped pathway for electrons (the battery counts as a pathway!).

The Requirement of a Closed Conducting Path

There are two requirements which must be met to establish an electric circuit. The first is clearly demonstrated by the above activity. There must be a closed conducting path which extends from the positive terminal to the negative terminal. It is not enough that there is a closed connecting loop; the loop itself must extend from the positive terminal to the negative terminal of the electrochemical cell. An electric circuit is like a water circuit at a water park. The flow of charge through the wires is similar to the flow of water through the pipes and along the slides of the water park. If a pipe gets plugged or broken such that water cannot make a complete path through the circuit, then the flow of water will soon cease. In an electric circuit, all connections must be made and made by conducting materials capable of carrying charge. Metallic materials are conductors and can be inserted into the circuit to successfully light the bulb. There must be a closed conducting loop from the positive to the negative terminal in order to establish a circuit and to have a current.

Current Flow and Direction
"Conventional Current Flow" vs. "Electron Flow" - This has to do with how circuit diagrams are interpreted. Now, remember we said that electrons are 'flowing' in the wires? The question here deals with : Do they 'flow' from the positive end of the battery, or the negative end of the battery?

Conventional current flow, devised by Benjamin Franklin, has the moving particles (later called electrons) positively charged. Therefore, this concept holds that electrons flowed out of the positive end of the battery. Electron flow, on the other hand, deals with the ACTUAL route of the electrons - being negatively charged particles, they go through the negative end of the battery! They then flow around the whole circuit, la la la, and arrive back at the positive end. Capeesh?

Current
'''-But Demosthenes, I don't get it. What's current? What are all these positive and minus things?'''

Why thank you for your hypothetical question, my reader, because this is the next thing we should understand: electron flow. What is an "electron?" To put it simply, an electron is an atomic particle which carries a negative charge. These electrons spin around the nucleus of an atom, which has a positive charge, and is located in the very center of the atom. The concept of "electricity" has to do with these electrons and with their "electron flow." Do you remember the example of our battery? This battery takes these negatively charged electrons from a chemical reaction inside the battery, pushes them out of the negative end of the battery, and into the wire. These electrons will then bump electrons in the atoms of the wire over and over until finally electrons arrive back at the positive end of the battery. Elements which allow this process of "bumping" those electrons on over determines how conductive the element is. So, when there's a current, it's just electrons bumping each other from atom to atom and flowing on.

-Oh, so I get it Demosthenes, you could just put a wire onto one end of a battery, and the electrons would still bump each other?

No, you could not. As stated before, in our definition of the circuit, a continuous loop is required. But think about it scientifically: If you did attach the wire to only one end of the battery, where would the electrons go that got bumped to the opposite end of the wire? That is why there needs to be that continuous loop of wire: the electrons need somewhere to go.

Voltage, Resistance, Power, Ohm's Law, and Amperes
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