1. Electric Current
Chapter 34

2. Flow of Charge Electricity (charge) Flow of electrons
Caused by electric potentials (differences in charge)
Charge will flow from negative to positive end

3. Electric Current Flow of electric charge per time (I= q/t)
Movement of electrons
Conductors have electrons that are free to move
Measured in amperes (A)

4. Voltage
Provides “electric pressure” (force per area) to move electrons between two terminals in a circuit
Causes current
Measured in volts (V)

5. Electric Resistance Resists to the flow of charge
Dependent on conductivity (inversely) and thickness of wire (inversely) as well as temperature (direct)
The longer the wire, the more resistance
The thinner the wire, the more resistance
Measured in Ohms (Ω)

6. Ohm’s Law Current= voltage resistance
The greater the resistance, the less the current
The greater the voltage, the greater the current

8. Types of Current Direct current (DC) Alternating Current (AC)
Flow of charge always flows in one direction
Example: batteries (have negative and positive
Alternating Current (AC)
Electrons in the circuit move first in one direction and then in the opposite direction
Example: electricity through your home
3 wires (+, -, neutral)

9. Source of Electrons in a Circuit
Source of electrons does not come from a power outlet but from the conducting circuit material (wires)
Energy flows from outlets to the circuit causing electrons to move

10. Electric Power
Rate at which electrical energy is converted into another form of energy
Electric power = current x voltage
Measured in Watts (W)