SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
ELECTRICAL CIRCUITS
All you need to be an inventor is a good imagination and a pile of junk.
-Thomas Edison

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
Would This Work?

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
Would This Work?

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
Would This Work?

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
The Central Concept: Closed
Circuit

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET circuit diagram
Scientists usually draw electric circuits using symbols; cell lamp switch wires

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
• Series circuit
– All in a row
– 1 path for electricity
– 1 light goes out and the circuit is broken
• Parallel circuit
– Many paths for electricity
– 1 light goes out and the others stay on

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
1
2
3

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
PARALLEL CIRCUIT
• Place two bulbs in parallel. What do you notice about the brightness of the bulbs?
• Add a third light bulb in the circuit. What do you notice about the brightness of the bulbs?
• Remove the middle bulb from the circuit.
What happened?

SmithStephanie Saturday, September 7, 2013 12:35:37 PM ET
Series and Parallel Circuits
• Series Circuits
– only one end of each component is connected
– e.g. Christmas tree lights
• Parallel Circuits
– both ends of a component are connected
– e.g. household lighting