1. Electric Current
Chapter 7 section 2

2. Electric Current
Electric current- The flow of electrons through a wire or any conductor.
Measured in units of Amperes (A)
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. Resistance
Resistance- the tendency for a material to oppose the flow of electrons, changing electrical energy into Thermal energy and light
Resistance is measured in Ohms (Ω)
Making wires thinner, longer, or hotter increases the resistance
Ohm’s Law- the current in a circuit equals the voltage difference divided by the resistance I = V/R

4. Electrical Circuits
Less resistance means less heat, which is safer for use in your home
As resistance increases, current decreases
As voltage difference increases, current increases

5. Sources of Electricity
A Dry Cell battery produces a voltage difference between its zinc container and its carbon suspension rod, causing current to flow between them.

6. Sources of Electricity
A Wet Cell battery contains two connected plates made of different metals in a conducting solution- like a car battery
Electrical Outlets- have a voltage difference across the two holes of an electrical outlet and a generator at a power plant provides the voltage difference
Resistance- the tendency for a material to oppose the flow of electrons, changing electrical energy into Thermal energy and light

7. Electrical Circuits
Series circuit- current has only one path to flow through
Parallel circuit- current has more than one path 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