Physics of Lightning Essay -- physics lightning thunder weather

In ancient times, lightning was seen as a tool of the gods. In Viking legend, it was Thor’s hammer striking an anvil in the sky that was responsible for lightning. For the Greeks, it was Zeus who threw lightning down to the earth. North American Indian tribes thought that lightning was produced by a mystical bird with flashing feathers whose flapping caused thunder. Even now, hundreds of years after the first scientific work with lightning, people remain in awe of its power. In the 18th century, the first systematic scientific study of lightning was carried out by Benjamin Franklin. Before Franklin’s experiments, electrical science had grown to the point of separating positive and negative charges, and had developed primitive capacitors. The sparks produced in laboratories were noted as similar to lightning, but it was Franklin who designed an experiment to prove that lightning was electrical. Benjamin Franklin believed that clouds must be electrically charged, which would mean that lightning must also be electrical. For his first experiment, he stood on an electrical stand with an iron rod in one hand to achieve an electrical discharge between the other hand and the ground. If Franklin’s belief that the clouds were electrically charged was correct, then sparks should leap between the iron rod and a grounded wire held by and insulating wax candle. This test method was published in London and performed in both England and France. Thomas Francois D’Alibard of France was the first to successfully perform this experiment in May of 1752, when sparks were seen jumping from the iron rod during a thunderstorm. Before Benjamin Franklin achieved results from his first experiment, he devised a better way of testing his hyp... ...wave). Lightning is often seen long before its thunder is heard. This is because sound travels at about 343 m/s though air, much more slowly than 3.00x108 m/s, the speed of light. While a lightning strike takes less than a second to complete, the sound of its thunder often lasts much longer. There are many reasons for this. The shape of the lightning bolt is a major factor, as all parts are not an equal distance from the listener. Sound produced by closer portions of the bolt will be the first of the thunder a listener hears, and sound produced by portions of the bolt that are farther away will be heard later. Another factor is that objects on the ground interfere with the sound, and echoes from hills and other objects can perpetuate thunder. Often lightning occurs in groups, so the sounds from multiple bolts sometimes overlap to cause longer lasting thunder.