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Feb pp 06 quiz.qxd 1/19/2006 1:05 PM Page 2 Energy Feature Using electricity safely and efficiently Test Your Electricity Knowledge Why can a bird sit on a power line and not be electrocuted? Because it is not touching the ground or any other grounded object. True or false: It is safe to climb a tree located near a power line as long as the limbs are not touching the line. False. Electricity has the ability to “jump” from the power line to the tree and electrocute someone in the tree. Never climb a tree near a power line. What is the best conductor of electricity? Silver. If you see a downed or low-hanging power line, what should you do? Stay clear and call your electric utility immediately. Where is the safest place to be during an electrical storm? By far the safest place to be is in a building or house. The metal plumbing and wiring in the walls form a protective barrier. However, do not touch and stay away from electrical appliances, plumbing fixtures and wiring. 6 FEBRUARY 2006 Is using a telephone during a lightning storm dangerous? Yes. Lightning can strike phone and electrical wires and travel into your house through your phone cord, and into your handset. Cordless phones do not pose the same risk because they have no physical connection to the wires. Is it OK to store flammable materials near wall switches or power equipment? No. A spark could jump unexpectedly. True or false: It is unsafe to touch a power line with a pole, even if the pole is made of plastic. True. Do not touch a power line with any object. How fast does electricity travel? At the speed of light: 186,300 miles per second. True or false: It is dangerous to leave a radio or other electrical device connected to a nearby electric outlet while bathing, even if the cord is insulated and the power is off. True. Water can conduct an electrical shock whether or not the cord is insulated or powered. What is the average number of people who die in the United States each year from being struck by lightning? About 100. True or false: A car is a safe place to be in an electrical storm because it has rubber tires. False. While an enclosed metal car is a safe place to be, the tires do not protect you. They would have to be about a mile thick and made of solid rubber to afford you adequate protection. The metal that surrounds you affords the protection. Lightning—like all forms of electricity—will travel only on the surface of enclosed metal objects. A 4,000-watt portable generator is big enough to power which of the following equipment: a refrigerator/freezer, an electric water heater and/or a 20,000 Btu air conditioner? The refrigerator/freezer and the water heater. A 20,000 Btu air conditioner typically requires more than 7,000 watts to start. Generators must be rated large enough to power the starting wattage of the entire load of equipment connected to them, not just the running wattage. True or false: It is safer to leave an extension cord out in the open than it is to run it under a rug. True. If a cord runs under a rug, you cannot inspect it for damage, and an overheated cord can ignite the floor covering. How much voltage is needed to hurt someone? Any amount of voltage can hurt or kill a person. True or false: Power lines are insulated and safe to touch. False. Most electric lines are bare. Overhead power lines and lines from a pole transformer to your home may be partially insulated, but even they are dangerous to touch. Stay away from them. ■ Adapted with permission from Colorado Country Life.