Science With Sabrina: Christmas Light Circuits

The countdown to Christmas is on, and so is turning on the holiday lights. But, once you flip the switch, do you ever notice how part of the strand isn’t working? Meteorologist Sabrina Bates explains why using circuits in this week’s Science With Sabrina.

Any type of light flows an electric current. In a closed circuit, electricity will travel through and cause the light to glow. But, what if the circuit is open, or broken? Then no electricity will flow through and the light won't be illuminated.

Christmas lights are similar, except there's obviously more than one light. To connect multiple lights to one power source, the lights need to be attached in series or in parallel.

We're creating our own circuits using old Christmas lights, foil, tape, and batteries.

First, let's create lights in series. Tape down the folded pieces of foil and connect the cut lights to them. Place a battery on the foil, and it lights up! When the lights are attached, electricity flows from one light to the next light until it reaches the power source. If one bulb blows out, all of the lights go out. 

Now, let's create lights in parallel. Each light has it's own power source. So, if one light blows, it doesn't affect the rest.

Onto the Christmas strands we know and love: some holiday lights are neither one way or another. Lights in series and in parallel are connected together. With this method, only a section of lights will go out, instead of them all. 

Segment Sponsored By: Sylvan Learning


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