Funny Little Symbols What do they mean?

Wire

Ammeter Voltmeter A V

Resistor

Light Bulb

Battery + -

Ground

Potential Difference (∆V) The difference in electric potential (voltage) between two points. Free charges flow when there is a difference and continue until both points reach a common potential. Flow from high potential (+) to low potential (-) Measured in Volts (V)

Charges Flow from high potential (+) to low potential (-) Does anybody have a problem with that? What are the charge carriers? Think of the + terminal as having a higher concentration of charge carriers (electrons and the – having a lower concentration of charge carriers (electrons). Then conventional current makes sense!

Current (I) The rate of flow of electric charge—how much charge passes a particular point in a given amount of time. Measured in Amperes (A). An ampere is equal to a Coulomb/second.

Resistance (R) The ability of a material to resist the flow of current through it Measured in Ohms (Ω)

Series Circuit Circuit whose devices are arranged so charge flows through each in turn. If one part of the circuit stops the current, it will stop throughout the circuit

Parallel Circuit Circuit whose devices are connected to the same two points in the circuit. Any individual device completes the circuit independently of the others

Water pipe analogy

Toll booth analogy