1. Electric Current

2. Electrical Current
Current is defined as the charge that flows over time
We use the variable “I” for current. The units are Amperes, which we use the letter A
Amperes are charge over time (C/s)

3. Electrical Current
Charge flows from one place to another when there is a potential difference, or difference in the voltage between the ends of a conductor
Charge will continue to flow until there is no difference between the potentials on the conductors

4. Electrical Current
Electric charges flow from high potential to low potential
Just like mass moves from high potential to low potential
Just like fluids move from high pressure to low pressure

5. Electrical Current
In solid conductors electrons carry the charge for current as they are allowed to move freely through the conductor.
In fluids, both the positive and negative ions as well as electrons move as current.

6. Electrical Current
Something that provides a potential difference is a voltage source.
Batteries and generators are capable of maintaining a steady flow of charges as they move from high to low potential.
Batteries supply the energy that allows charges to move.

7. Electrical Current
The amount of current that flows through a circuit depends on the voltage provided by the voltage source and the resistance the conductor (or wire) offers
The resistance of a wire depends on the resistivity of the wire
Resistance is measured in Ohms (Ω)

8. Voltage = Current x Resistance
Electrical Current
Ohm’s Law – the current in a circuit is directly proportional to the voltage driving the circuit
𝑉=𝐼𝑅
Voltage = Current x Resistance
The greater the resistance, the less the current.

9. Electrical Current
Worksheet
Then go to page 545 # 5, 7, 12, 26, 28