Atoms and Electricity All matter is made of atoms. Atoms are made of protons, neutrons, and electrons. Electrons orbit the nucleus of an atom. Electrons can be added and/or removed from an atom. Electrons cannot occupy the same space at the same time.

Atoms and Electricity therefore, when electrons move from one object to another it causes the electrons in second object to move. The rapid movement of electrons is referred to as electricity.

Electricity Electricity results from a flow of charges that may be negative or positive. Material that allows electrons to flow are called conductors (all metals are conductors and some better than others) Material that does not allow electrons to flow are called insulators (rubbers,paper, and plastics are some examples)

Insulators and Conductors Internal friction involves the restriction of electrons from flowing in an object. Insulators and conductors both have internal friction associated with them. However, conductors have significantly less internal friction than do Insulators.

Types of Electricity Static Electricity: A build up of charge on an object (the electricity does not flow. It stays stationary until transferred). Charging can result from friction or contact. Current Electricity: A process in which electrons flow from one point to another through a conductor

Current Electricity Current Electricity results from charges (e - ‘s) moving from one place to another through a conductor. Current electricity can travel through two basic types of circuits (Parallel and Series)

Circuits: Series vs. Parallel Series Circuit Parallel

Series vs. Parallel Circuits Name two things that are common between the two. The basic parts (resistor, switch, potential difference source (battery) Name two things that are different b/t series and parallel circuits. (They both have a different # of electrical loops. They offer different amounts of energy) What would be the advantages and disadvantages of using series or parallel circuits in a home.

Calculations Resistance (R) the amount of internal friction in a material that is measured in a unit called Ohms (omega) Current (I) the measure of the flow of electrons that is measured in Amps (A). Voltage (V) the measure of the potential difference source (the push behind the electrons) that is measured in Volts (V).

Calculations Electrical Power (P) is the measure of how much electrical current is required by appliance to function.

Basic formulae and calculations Resistance (R) = Voltage (V) / Current (I) Power (P) = Current (I) x Voltage (V) Power (P) = (Current) 2 (Resistance) What would these look like like in triangle form ?

Let’s Make Calculations See textbook page 443 (1-4) See textbook page 451 (1-5) See textbook page 452 (1-8) Use the GUESS method