![]() You can see how the electric field lines get concentrated at the pointed surface. If one surface is pointed then the field lines will appear to be as shown. If two plates are kept parallel and one is charged positively and the other is charged negatively, the electric field lines will be straight lines perpendicular to the surface. Thus a pointed object leaks or accepts charges more readilyĬonsider the second condition of electric field lines. It can be seen that the density of charges at the pointed edge is more. Surface and a pointed surface will have different charge distribution. As a body narrows the charge per unit surface area increases. At any given time the electrons are distributed over the outer surface of a charged body. Two surfaces with different potential along which a charge will be able to flow.Ĭonsider a surface that has acquired negative charges due to rubbing. And secondly we have to know how the electric field is distributed between two charged bodies. First we have to know how charges are distributed in a body. To answer this we have to consider two aspects. Have lightning rods placed on their roofs. In an open county side even low height houses This is the reason why most of the high rise buildings and tall towers are equipped with lightning rods. The low level buildings are therefore relatively safer. Thus a lightningĭischarge can damage them first. This gives an easy close path for the charges built up in the clouds. They are at a ground potential and they come closer to the charged clouds. In an urban area, high rise buildings are more at a risk for a lightning strike. The conductor quickly makes the charges flow down to the earth and the house is saved from any damage. Roof so that if lightning strikes, it strikes the conductor before it can reach the house. The lightning conductor is placed higher than the That is, it is earthed or grounded properly. In the figure below you can see that the cloud is negatively charged and it induces a positive charge on the house including the lightning conductor.Ī lightning conductor is made up of a sharp pointed metal (usually copper metal, as it is a very good conductor) connected directly to the ground. This phenomenon makes some clouds positively charged and some clouds negatively charged.Ī negatively charged cloud will tend to induce a positive charge in the local areas around itself. But as the mass of cloud increase in size, they start rubbing against each other. Moisture bearing clouds are initially electrically neutral. These charges discharge towards another body (may be the earth, a building or another cloud), which is at a different potential. They often resemble sticks, since the outside usually looks like tree bark because it's made of partially-melted sand.Lightning occurs due to the build up of static electrical charges in clouds. If you look for fulgurites, don't expect to find something resembling a transparent tube. They're usually one to two inches in diameter and only a few inches long, although some fulgurites can reach two feet or more in length. Unfortunately, fulgurites are brittle and delicate, so they're easily broken if you dig for them. Since they're created underground, you either have to dig for them or stumble across one that happens to have been unearthed by erosion. The word comes from the Latin word for "thunderbolt." They're also sometimes known as petrified lightning.įulgurites can be found all over the world, but they're not very common. Scientists call these creations fulgurites. ![]() This creates hollow, glass-lined tubes that are rough and sandy on the outside. When it strikes sand, it can actually create interesting works of art if the conditions are just right.įor example, if lightning strikes sand that's rich in silica or quartz and heats it to a temperature above 3,272˚ F, it will melt the sand into silica glass below the surface. The sounds of thunder and the awesome lightning displays should only be experienced from a distance, as it can be very dangerous to be near a large body of water during a lightning storm.Ī bolt of lightning packs awesome power and can even be hotter than the surface of the Sun. Storms that blow in from the ocean can be fierce at times. It can be frustrating when storms come and force you to stay inside when you just want to feel the sand under your toes. There's nothing like hours and hours of floating in the ocean waves and soaking up the Sun's rays to relax the body, mind, and soul.īeach vacations are a lot of fun as long as the weather is cooperating. Others might opt for a " staycation" close to home.įor many families, though, a summer vacation means a trip to the beach. Does your family take a summer vacation each year? Many families like to pack up the family vehicle for a cross-country road trip to visit several national parks.
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