Definition The rate at which charges pass a given point

Units of measurement Amperes Shortened to Amps

2 Types of Current DC▪ AKA: direct current▪ Electrons always flow in the same direction.▪ Batteries in a camera or a flashlight use DC

AC▪ AKA: alternating current▪ The electrons can move in either direction▪ Electrical outlets in your home use this.

Definition The measure of how much work is needed to

move a charge between 2 points. Units of measurement

Volts (V) Relationship between voltage and current

As long as there is voltage between 2 points on a wire, charges will flow in the wire.

The greater the voltage:▪ The greater the current.

Different batteries have different voltages Car batteries need a bigger current to start the

car so they have a higher voltage.

1.5 Volts

9 Volts

6 Volts

Definition The opposition to the flow of electric charge Like “electrical friction”

Units of Measurement Ohm’s Represented by the Greek letter omega ( )

Variables which affect resistance Material ▪ Good conductors have a:▪ Low resistance▪ Like Copper

▪ Insulators have a:▪ High resistance

Temperature▪ As you increase a metals temperature▪ You increase resistance

▪ Superconductors▪ Metals at very low temperature who’s resistance is virtually 0

Definition: These change chemical or radiant energy into

electrical energy Parts

Electrolytes▪ Mixture of chemicals which allow charges to flow

Electrodes▪ Made of conductors▪ Points at which charges enter and leave the cell.

2 Types Dry Cell▪ Electrolytes are solid or paste▪ Normal batteries

Wet Cell▪ Electrolytes are liquid▪ Car batteries

Ohm’s Law Relates current, voltage, and resistance Voltage = Current X Resistance V = I X R

Electrical Power Power = Voltage X Current P = V X I Measured in Watts