Lightning Dictionary DefinitionAn abrupt, discontinuous natural electric discharge in the atmosphere. Back to TopFormationExplanationThere are several different ways for lightning to form, but they all involve neutralizing atoms. Read the Electricity section to learn more about atoms.
Experiment #1: ElectroscopeWhat You'll Need:
Directions:
What's Happening?When the pen is near the foil, negative charges are drawn up the wire to the ball to counter the positive charges of the pen. When this happens, the candy wrapper is left with only positive charges. Both parts of the candy wrapper have the same charge, so they fly apart. Back to TopTypes
EffectsLightning actually helps nature because it makes nitrogen available to plants. Although nitrogen is abundant in the atmosphere, plants cannot absorb it very easily when it is pure. A lightning flash emits a lot of energy that creates a chemical reaction to combine nitrogen and oxygen, creating compounds called nitrates. These compounds can then be absorbed by plants when they fall to the ground. Lightning is dangerous, killing around four hundred people in the United States each year. Most of the deaths occur when the people are out in open, exposed locations. Lightning also injures another one thousand people, who suffer from electric shock and burns. Lightning also causes forest fires. These fires can be beneficial, however, because they destroy deadwood and excessive undergrowth and allow the nutrients of these to return to the soil. Some plants even need a fire to release their seeds. This used to be a natural life cycle for the forest, but now we must fight these fires to save property nearby. Back to TopDiscoveryBenjamin Franklin opened up the investigations by concluding that the spark produced by "electrical fluid" was like lightning in many ways. He tested this idea of his with an extremely dangerous experiment. To see if he could make the lightning come to a sharp point, Franklin made a kite covered in silk and attached a wire to it. He tied a long linen string to it with a silk ribbon at the end of the string. Then he attached a key to the string where it was attached to the silk ribbon. He then flew it during a thunderstorm, expecting to get an electric charge carried along the string along the good conductor of wet linen thread and remain protected by the insulator of dry silk. He flew the kite during the thunderstorm, and drew sparks from the key. He then concluded that lightning was a giant electric spark. Benjamin Franklin took the precaution of standing under a shed where he and the silk ribbon wouldn't get wet so that the dry silk would do its insulating work. However, several more people attempted to try Franklin's kite experiment and were struck by lightning (so therefore: Don't try this at home). Charles Proteus Steinmetz, an engineer for General Electric Company, began making artificial-lightning generators to study its effect. He used an electrical condenser to store a huge electric charge, like a cloud. When it reached a certain point, the electricity created an enormous spark. They could then study how lightning strikes on models of buildings and trees. After Steinmetz died in 1923, larger and more powerful generators were built that helped scientists learn more about lightning and take precautions against it. In 1935, metal rods were set up on the Empire State Building in New York City to see what happened when lightning struck such a tall structure. The lightning hit the rod at the top of the building, which was connected to the steel frame of the structure, and traveled harmlessly to the Earth. Some of the lightning current was also diverted from the rod to instruments that recorded the shape and other characteristics of the stroke, while cameras recorded the flash. From these experiments, they disproved the theory that lightning never strikes twice in the same place because the Empire State tower has been struck by lightning as many as forty-two times in one year. One storm hit the tower twelve times, and another hit it twenty times in nine minutes. However, none of these strikes has damaged the building. Back to TopElectricityExplanationAn atom has a nucleus at its center that has positively charged particles called protons, and neutral particles called neutrons. Negatively charged particles, called electrons, revolve around the nucleus in rings. Usually, there are an equal number of protons and electrons in an atom, and they cancel each other out so there isn't an electric charge. When the atom is like this, it is neutral. However, when an atom gains or loses electrons, it aquires a charge. If it gains electrons, it is negative, and if it looses electrons, it is positive. When a negatively charged object touches one that has a positive charge, the electrons flow from one to the other to equalize it and make them neutral again. If the charges are great enough, the objects do not need to come into contact because the electrons will jump across the space separating them. When this happens, a spark is created. When lightning is created, it makes a spark sort of like this. The electric charge in lightning can be demonstrated by the experiment below, which shows that lightning affects radio waves. Back to TopExperiment #2: Radio WavesWhat You'll Need:
Directions:
What's Happening?The resulting pop that comes from the radio is like the crackling sound of static during a thunderstorm because both are caused by radio waves. The static sound of the thunderstorm comes from the electrical charges in lightning, whereas the popping sound is produced by the electrical charge on the balloon. Back to TopProtectionThere are many ways to help protect yourself from lightning. Inventions, common sense, and the rarity of lightning strikes will help you avoid lightning.
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