Electricity.

Ten Important Things About Electricity

1) Difference between a Conventional Current vs. Electron Flow

Conventional current: movement of positive charge flow where the flow travels from the positive terminal to the negative.

Electron Flow: movement of electrons from the negative to positive terminal and the negatively charged electrons are repelling each other.

2) Current

Current is represented by (I) and is the rate of  charge flow and is measured in Amperes (A). 

It is calculated by dividing Charge (Q) by Time (t) in seconds. ---> I= Q/t

Charge is represented by Q and is the total amount of charge moving past a point in a conductor and is measured in Coulombs (C).

3) Voltage

Voltage is represented by (V) and it is the electric potential energy for each coulomb of charge in a circuit. Another name for Voltage is electric potential difference. It is measured in volts (V). 

It is calculated by dividing Energy (E) by Charge (Q). ---> V= E/Q or V= W/Q

(E) is energy required to increase the electric potential of a charge and it is measured in Joules.

4) Energy

The energy delievered to a load depends on the potential energy by charge and the rate of the charge that is being delivered (current).

Energy transferred by charge flow is calculated by : E= VIt (Voltage*Current*time)

5) Measurement using a Anmeter and Voltmeter

An anmeter is a device that measures current (I) and it must be wired so that all current flows through it. This anmeter should be a exceptional conductor so that no energy is lost. It must be wired in Series with the Circuit.

A voltmeter is a device that measures Voltage (V)which is the potential difference between any two points. The voltmeter, unlike the anmeter should be a poor conductor and have a high resistance so that it is less than the load it is connected to so that the measurement by the voltmeter directs less of a current from the circuit it is connected to. The Voltmeter must be connected in parallel with the load (before and after).

6) Ohm's Law
The measurement of the opposition of flow is called resistance. Resistance is represented by (R) and is measured in Ohms. It is the relationship that connects Current, Voltage, Resistance, and Power. It can be calculated according to a pyramid chart.

where R= V/I, V= IR, I= V/R

7) Kirchhoff's Law

*This law applies to both series and parallel circuits.

i. Current Law states that the total current flowing into a connection equals total current flowing out a connection.

ii. Voltage Law states that the algebraic sum of the potential differences around a closed pathway equal zero.

8) Series and Parallel Circuits

In a Series Circuit, charge flows along one path. The equations for a series circuit are:

I total = I1=I2=I3=...In

V total = V1+V2+V3+...Vn

R total = R1+R2+R3+...Rn

In a Parallel Circuit, charge flow along two or more paths. The equations for a parallel circuit are:

I total = I1+I2+I3+...In

V total = V2=V2=V3=...Vn

1/R total = 1/R1+ 1/R2+ 1/R3+ ...1/Rn

9) Power ( watts)

P=IV , P=V2R, P=I2R

Cost: P (in kW). t(hours). cost rate

10) Energy ( joules)

E=VIt