LED circuit using a graphite pencil
Can you complete an LED circuit using a graphite pencil? Learn about the conductive properties of graphite and draw your own design to see it light up! This is a super quick and easy science experiment that is entertaining for both kids and adults alike.
How we did it:
Use your graphite pencil and draw any design on your paper.
Tip: Draw a simple image where all the lines are connected and make sure to create thick, bold lines with your pencil.
In your drawing, leave at least a 1 cm gap on opposite ends of your drawing. Mark your positive and negative lines.
Once you’re done with your design, place the battery on one of the gaps. Align the positive and negative ends with the graphite lines.
Take an LED and bend the bottom ends of the wires.
Tape the wire at the end of the lines across the other gap, aligning positive and negative wires. Make sure your LED stands upright. The wires should be in contact with the graphite lines.
Tip: The longer side of the LED is the positive side.
What’s going on?
Graphite is an electrical conductor, perfect for learning about circuits and electricity! Because graphite is low in conductivity, the success of a circuit will depend on the length, thickness, and amount of graphite on the paper. For example, the longer the graphite path is, the dimmer your light will be.
It’s time to experiment! Try drawing lines of different lengths. Does it make a difference to the LED? Try drawing lines of different thicknesses. Does that make a difference to the LED?