How can 1 wire, 1 battery, and 1 bulb be used to make a complete circuit?
What about 2 wires, 1 battery, and 1 bulb?
Pathfinders
For the device to work, the electrical energy must flow in a complete or closed circuit.
Circuit Diagram
Basic circuits require the following components:
• An energy source (electricity or a dry cell)
• A conductor (usually a wire or something made of metal)
• A device to operate (resistor)
Basic Circuits
Connect 1 bulb to your batteries
• Draw a diagram and write one sentence describing what happened.
Connect a total of 2 bulbs to your batteries
• Draw a diagram and write one sentence describing what happened.
Connect a total of 3 bulbs to your batteries
• Draw a diagram and write one sentence describing what happened.
Series Circuits (L)
What happened as you added more bulbs to your series circuit?
Why do you suppose that is?
How many paths does the electrical current have to flow through?
Stop and Think
What do you think would happen if we removed a bulb from a series circuit?
1. Set up a series circuit with 1 bulb.
2. Now, come and pick up a bulb holder with the bulb removed.
3. What happened to the other bulb?
4. Why?
Removing a Bulb
• Series circuits have one and only one path for an electrical current to flow through.
• The current flows through every part of the circuit.
In a complete series circuit, the more bulbs or devices that are added, the ____________________________
____________________________________________.
If one bulb is removed, then _____________________
____________________________________________.
Series Circuits (R)
Toys that use batteries
Cell Phones
Computers and Tablets
Blenders
Televisions
Holiday Lights (old fashioned)
Any others??
Series Circuit Examples
Make a series circuit with 1 bulb
• Draw a diagram and write one sentence describing what happened.
Making Parallel Circuits
Make a series circuit with 1 bulb.
Next, connect a total of 2 bulbs to your battery like this:
• Draw a diagram and write one sentence describing what happened.
Parallel Circuits (L)
Now add a third bulb in your parallel circuit like this:
• Draw a diagram and write one sentence describing what happened.
Parallel Circuits (L)
What happened as you added more bulbs to your parallel circuit?
Why do you suppose that is?
How many paths does the electrical current have to flow through?
Stop and Think
What do you think would happen if we removed a bulb from a parallel circuit?
1. Set up a parallel circuit with 2 bulbs.
2. Now, come and pick up a bulb holder with the bulb removed. Swap it out with one of the bulbs in your parallel circuit.
3. What happened to the other bulb?
4. Why?
Removing a Bulb
• Parallel circuits have more than one path for an electrical current to flow through.
• Have at least one point where the current divides or splits into different branches.
In a complete parallel circuit, the more bulbs or devices that are added, the ________________________________
________________________________________________.
If one bulb is removed, then _________________________
________________________________________________.
Parallel Circuits (R)
School and business lighting and outlets
Household lighting and outlets
Electrical wiring in cars
Microwave
Refrigerator
Holiday lighting (newer strands)
Any others??
Parallel Circuit Examples