ELECTRICITY REVIEW 1 THE BASICS Electricity Describes all

ELECTRICITY REVIEW

1. THE BASICS… Electricity: � Describes all phenomenon related to electrical charges (positive and negative) � Electrical charges: Protons are positively charged Electrons are negatively charged

1. THE BASICS… Electrical Charges � Measured in coulomb (C) � Like electrical charges repel each other � Opposite electrical charges attract each other � Electrical charged can neither created or destroyed only transferred (law of conservation of charge)

1. THE BASICS … Conductor: � Substance Metals, salt water Insulator: � Substance that allows the flow of electricity that does not allow the flow of electricity Wood, plastic, glass, paper Semi-Conductor: � Sometimes Carbon allows the flow of electrons

Hi, I am a conductor. You may pass. Hi, I am an insulator. And like Gandalf…

2. STATIC ELECTRICITY Describes all the phenomena related to electrical charges at rest

2. STATIC ELECTRICITY 1. Friction: � 2 neutral objects � Electrons are pulled from one object to another � Ends with 2 oppositely charged objects

2. STATIC ELECTRICITY 2. Conduction: � 1 charged object, 1 neutral object � The charges are shared � 2 objects of similar charge

2. STATIC ELECTRICITY 3. Induction � 1 charged object, 1 neutral object � The proximity of the charged object causes the charges in the neutral object to seperate � End with 1 charged object and one partially charged object

3. DYNAMIC ELECTRICITY Describes all phenomena related to electrical charges in motion Electrical current: � Orderly flow of electrons

Characteristics Definition of electrical Unit Symbol Current Intensity Number of charges that pass a specific point in a second Ampere (A) I Potential Difference The amount of energy transferred between two points in an electrical circuit Volts (V) V Resistance Ability of a material to slow the flow of electric current Ohm ( Ω ) R

3. DYNAMIC ELECTRICITY Ohm’s law: �V = RI � For the same resistance, the potential difference is directly proportional to the current intensity Electrical power: � The amount of work an electrical device can perform per second � Measure in Watt (W) � 1 W = 1 J/1 s

Ohm’s law: �V = RI � For the same resistance, the potential difference is directly proportional to the current intensity = V=RI

4. ELECTRICAL FORMULAS V=R I P=VI E = P ∆t V= Potential Difference R = Resistance I = Intensity P = Power E = Energy ∆t = time

5. CIRCUIT DESIGN An electrical circuit is a network in which electrical charges can flow continously in a loop Basic requirements � Power supply: gives energy to the circuit � Electrical resistance: uses electrical energy � Wires: carries the charges

5. CIRCUIT DESIGN Series Circuit Parallel Circuit Only one pathway All elements are connected one to another All elements are dependant on one another Multiple pathways Elements are connected on different pathways Elements are independant of one another