Summer Science Series: Play Dough Circuits

Did you know?

Play Dough can be used to conduct electricity!

Let’s take our Summer Science Series up a notch! If you’ve completed the first couple of projects then you’re familiar with static electricity. We used it to make a butterfly’s wings flag and to seperate salt and pepper! This week we’re switching gears. Let’s use electricity and play dough to light up some LEDs! Did you know that play dough conducts electricity?! Complete the experiement below to find out why and see if it really works. Let’s check it out. 

You’ll Need:

Battery Holder Case with On/Off switch and wire leads. (Click Here)

AA Batteries

Light Emitting Diodes (LED) Bulbs (Click Here)

Play Dough (most regular play doughs will work) or Make Your Own with Squishy Circuits

Directions:

Step 1. If you’re making your own dough, do that now. (See the recipe above)

Step 2. Roll out two small logs of play dough. 

Step 3. Install batteries in your battery holder and make sure the switch is off. 

Step 4. Place the black wire lead into one of the small logs of insulating dough and the red wire lead into the other log of insulating dough. 

Step 5. Place an LED Bulb over top with the long (positive) prong in the log with the red wire and the short (negative) prong in the log with the black wire. Your LED Bulb should light up when you turn the switch on!  

Now you’re ready to make a Series Circuit:

Step 1. Use your play dough to make three small balls and line them up in a row. 

Step 2. Place the black wire lead into the ball furthest to the right. 

Step 3. Place the red wire lead into the ball furthest to the left. 

Step 4. Place an LED Bulb in between each ball with a prong in each. Current can only go through an LED one way, so you need to have the short (negative) side prong in the ball closest to the black (negative) wire lead and the long (positive) side prong in the ball closest to the red (positive) wire lead. The battery will push the electrical current from the positive side (long legs) out the negative sides and through our play dough. 

Now you’re ready to make a Parallel Circuit:

Step 1. Make two small-medium size logs of your conductive dough. 

Step 2. Place the red wire lead into one log. 

Step 3. Place the black wire lead into the other log.   

Step 4. Place two LED bulbs over the logs with the long (positive) prong in the log with the red wire and the short (negative) prong in the log with the black wire. 

Step 5. When you turn the battery pack on, both LED bulbs will light up. This is a Parallel Circuit. 

What’s that got to do with electricity? Play dough contains salt dissolved in water and salt conducts electricity so our dough also conducts electricity. Light emitting diodes (LEDs) light up when electricity flows through them (like a light bulb does). In the series circuits the electricity flows from the positive side to the negative side, but in a parallel circuit the electricity splits up and flows through each positive side to each negative side lighting up our LEDs.

We hope you enjoyed the project!