1. Electric Current

2. Electric Current
Electric current- The flow of electrons through a wire or any conductor.
Measured in units of Amperes (A)
Different from static electricity because it lasts longer
Charges flow from High voltage to Low voltage
Voltage difference- push that causes charges to move- measured in volts (V)
For charges to flow, the wire must always be connected in a closed path, or circuit

3. Electrical Circuits
Less resistance means less heat, which is safer for use in your home
Ohm’s law- current in a circuit equals the voltage difference divided by the resistance.
As resistance increases, current decreases
As voltage difference increases, current increases

4. Electrical Circuits
Series circuit- current has only one loop to flow through
Parallel circuit- current has more than one loop to flow through
Magnetic fields form around wires through which electricity is moving
Electromagnet- a temporary magnet made by placing a piece of iron inside a current-carrying loop of wire
More loops = stronger
More voltage = stronger
Only works for DC current

5. Resistance All materials have some electrical resistance.
Resistance is measured in Ohms (Ω)
Making wires thinner, longer, or hotter increases the resistance

6. Electrical Circuits
Circuits rely on generators at power plants to produce a voltage difference across the outlet, causing the charge to Flow when the circuit is complete
Series Circuit- the current has only one path to flow through

7. Series Circuits

8. Series circuit
The parts of a series circuit are wired one after another, so the amount of current is the same through every part
Open Circuit- if any part of the circuit is disconnected, no current flows
Example- old style Christmas lights

9. Voltage Source
Wire- conductor
Load- like a bulb
Switch

10. Parallel Circuit
Parallel Circuit- contains two or more paths for the current to move through

11. Parallel Circuits
Individual parts can be opened without affecting the entire circuit
Like the lights in your house
Household circuits are parallel circuits
Each branch receives 120 V from the electric company
Electrical energy enters your home at the circuit breaker or fuse box and branches out to wall sockets, major appliances, and lights

12. Circuits Guards against overheating electric wires:
Fuses- contain a small piece of metal that melts if the current becomes too high, opening the circuit and stopping the flow of current
Circuit breakers- contain a small piece of metal that bends when it gets hot, opening the circuit and stopping the current