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(NL) = not linked in sample site

Puzzle Board: Click on button above for larger image Puzzle board piece with bulb and batteries Two wires with alligator clips

Understanding closed circuits. Introducing circuit diagrams.

Examine the bulb holder. Find its contact points. How are the contact points of the bulb connected to the holder?

Draw pictures of a few bulbs. Mark their contact points. Show what glows in each bulb.

 

 

 

How would you turn the bulb off?

Does the bulb turn on when one wire is connected between the battery and the bulb on the puzzle board?

Because

The second picture uses symbols for circuit elements (NL) rather than pictures.

• The light bulb is indicated by the zigzag line, which is the symbol for a resistor.
• The symbol for a battery is a long line with a short line next to it. The long line indicates the + (or positive) side of the battery and the short line the - (or negative) side of the battery.
• Wires are indicated by lines that connect circuit elements.

Using a colored pencil, draw lines in the picture to show how you connected the wires in circuit above. This picture is called a circuit diagram (NL)

Draw arrows in the circuit diagram to show how the electron current flows

A closed path is needed for current to flow in a circuit. This is sometimes called a closed circuit or a completed circuit. You now have your circuit drawn in picture form and as a circuit diagram!