Try It Part 2
Continue reading and then determine how the author is revealing the text’s purpose through the use of text and visuals.
Read paragraphs 5 through 10 of the holiday lights article from Energy.gov Opens a new window and complete the follow-up activities.
Parallel vs. Series Lights
5 When lights are attached in series, the electricity passes from the power source to the first light, and then from light to light until it returns to the power source. In this setup, when a filament within any one bulb blows out, it creates an open circuit in the wiring. As we mentioned earlier, when a circuit is incomplete, or open, electricity fails to pass through any of the wire, causing all the lights to go out.
6 When lights are attached in parallel, each light is on its own circuit to the power source. If one filament burns out, it has no effect on the remaining lights, as they each continue to be in a closed circuit with the power source. Check out the difference.
7 With strings of holiday lights, engineers decided that the best option was to connect several series of lights together in parallel. In other words, holiday lights are both in series and in parallel. Let’s see what this looks like.
8 This way, when one series of bulbs becomes defective -- say from a loose bulb -- it should have no effect on any of the other series of bulbs, since they are in parallel to the defective series. This is why sometimes only one portion of your lights will become defective, while others will remain functional. When additional strings of lights are attached to the end of a string, these lights are added in parallel to the original strand.
9 But what about when a bulb goes out in series? It used to be that when one bulb went out the entire series would go out. If this were the case, you would have to check each bulb individually to see which one was blown out. If multiple bulbs were blown out, this would become exceedingly difficult.
10 Enter the "shunt." What is a shunt, you ask? I will tell you!
- Energy.gov - “How Do Holiday Lights Work?opens a new window”