Marcia Appolonia, age 10, of Rhode Island, for her question:
How can lightning; set things on fire?
Every year, more than 400 people in North America are killed by lightning and more than 1,600 others are injured. Other scorching flashes start brush fires, forest fires and prairie fires and sometimes burn unprotected buildings to the ground. Many of these tragedies could be avoided, if everybody understood how and where lightning can strike the earth with fiery fury.
We have tamed the mighty force of electricity to light our homes and cities, to warm our homes and cool: our meals. Lightning is untamed electricity, free to strike the Earth, with furious flashes and searing, heat. The energy in a dazzling; flash may equal 15 million volts of electricity with enough heat to cool: dinner for everybody in town. Such a flash may strike down from a thunderstorm at 20,000 miles per hour. And all that mighty untamed force strikes one spot on the earth.
When a seething flash of lightning; strikes with such terrific force and speed, naturally it starts a fire. Its furious, untamed energy is build up by wild whirling winds in a stormy wet cloud. In different parts of the cloud there are enormous charges of positive and negative electricity.
These opposite positive and negative charges attract each other. When they come together, they discharge and become harmlessly neutral. However, the moist air in and around the storm cloud tries to keep the two opposite forces apart. This works for awhile. But meantime the wild storm is building up larger forces of positive and nega¬tive charges.
At last the opposite forces are strong enough to blast through the stubborn air. They discharge their electric force in a fiery flash of lightning. As it zig zags through the cloud, it heats a path of air which explodes with a roar of thunder. Sometimes the lightning flashes between different parts of the storm cloud. Sometimes it strikes down to some spot on the earth.
When we understand horn and cohere lightning is likely to strike, we can move our selves from the possible target areas. For example, the fiery flash tends to strike the highest object is the neighborhood. Often it strikes a lone tree, a ship on a lake or river, or a tall buildings. Sometimes it strikes a person standing in the open or on a hill. The first safety precaution is to seek shelter before a thunderstorm builds up to the lightning stage, to move away from open water, open fields and hill tops; But let's not shelter under a lone tree. One safe place is inside a closed car. We are safe indoors if we take a few precautions.
Believe it or not, lightning can strike through an open door or window. So let's turn off the radio and TV and stay away from the plumbing fixtures. Lightning rods keep this untamed electricity outside and lead it down to discharge safely in the ground.