what is lightning,how does it occur and what are its effecs?
342819
In the process of the water cycle, moisture can accumulate in the atmosphere. This accumulation is what we see as a cloud. Interestingly, clouds can contain millions upon millions of water droplets and ice suspended in the air. As the process of evaporation and condensation continues, these droplets encounter many collisions with other moisture that is in the process of condensing as it rises. Also, the rising moisture may collide with ice or sleet that is in the process of falling to the earth or located in the lower portion of the cloud. The importance of these collisions is that electrons are knocked off of the rising moisture, thus creating a charge separation. \n\nThe newly knocked-off electrons gather at the lower portion of the cloud, giving it a negative charge. The rising moisture that has just lost an electron carries a positive charge to the top of the cloud. Beyond the collisions, freezing plays an important role. As the rising moisture encounters colder temperatures in the upper cloud regions and begins to freeze, the frozen portion becomes negatively charged and the unfrozen droplets become positively charged. At this point, rising air currents have the ability to remove the positively charged droplets from the ice and carry them to the top of the cloud. The remaining frozen portion would likely fall to the lower portion of the cloud or continue on to the ground. Combining the collisions with the freezing, we can begin to understand how a cloud may acquire the extreme charge separation that is required for a lightning stroke.
301729
Both are correct.\n\nDuring a lightning strike, leaders travel up from the ground or object that is about to be struck. At the same time a strike comes from the clouds downward.\n\nWherever the leader is the tallest, the two will meet.\n\nThere are several types of lightning...\nCloud to ground\nGround to cloud\ncloud to cloud\n\nall are correct
619415
From a distance, lightning will come before the thunder.  But at the point of the bolt, they occur at the same time.\n\nFrom the source below:\n"Actually, they do occur at the same time. The time difference that you sense is due to the way sound and light travel. Light travels extremely fast (300,000,000 m/s). In fact, it is faster than anything else. Sound travels at a measly 343 m/s through air. Therefore we can see light in an instant, but it takes a while to hear thunder."
44881
Don't think of Lightening as a form, think of it as a force.  The force manifests itself in that bright column as that force moves through the air.  Take a look at this video, not only is lightening not completely understood by science but our ideas about what triggers it are changing.
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Lightning causes thunder because a strike of lightning is incredibly hot. A typical bolt of lightning can immediately heat the air to between 15,000 to 60,000 degrees Fahrenheit. That's hotter than the surface of the sun!  \nA lightning strike can heat the air in a fraction of a second. When air is heated that quickly, it expands violently and then contracts, like an explosion that happens in the blink of an eye. It's that explosion of air that creates sound waves, which we hear and call thunder.  \n\nWhen lightning strikes very close by, we hear the thunder as a loud and short bang. We hear thunder from far away as a long, low rumble.  \n\nLightning always produces thunder. When you see lightning but don't hear any thunder, the lightning is too far away from you for the sound waves to reach you.  \n\nLight and sound will always move at different speeds. And lightning will always produce thunder because of a strike's high temperature. So no matter what, you will always see a flash of lightning before you hear thunder.
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Lightning are actually sparks produced when water molecules in the clouds rub against each other, producing friction and therefore heat.  This creates positive and negative charges and they always seek to attract each other.  (like a magnet)\n\nThus, lightning can acutally shoot anywhere it wants to, as long as there is a negative in one place and a positive charge in the other.  Lightning also tends to hit the closest object within range.  Contrast to popular belief, metallic objects do not attract lightning.  They just conduct the electricity better than other insulators, and of course, the shock will be greater.
548407
Yeah, it does...The truth is, lightning tries to find the shortest distance to ground (The Earth). Although the odds are favorable that lightning won't strike the same place twice, there is nothing in nature to prevent it. It can strike 3 or 4 times in the same spot.
785117
an Electrical storm involves lightning.\nAnd lightning can travel at the speed of light.\nBecause it mostly is light.\n\nThunder is slower and goes at the speed of sound so we hear the thunder later.
282569
ah ha my kinda question. lightning comes down only to a point above the strike point then a contacting point comes up from the strike point and connects with the down charge completing the circut. then the charge goes up and down several times. thats what causes the bright flash. here are some pages that will help.
199846
You are holding a metal rod...there is lightning all around. Metal rods attract lighting. You are holding a metal rod.
382607
Lightning is an electric current. Within a thundercloud, many small bits of ice bump into each other as they swirl around in the air. All those collisions create an electrical charge, just like the one that builds up in you when you cross a carpet.\n\nAfter a while, the whole cloud fills up with electrical charges (usually with a negative charge closest to the earth). Since opposites attract each other, that causes a positive charge to build up on the ground beneath the cloud. The ground's electrical charge concentrates around anything that sticks up, such as mountains, lone trees, people, or even blades of grass. The charge streaming up from these points eventually connects with a charge reaching down from the clouds, and--zap!--lightning strikes.\n\nThe intense heat of the lightning bolt causes the surrounding air to explode outward with a gigantic boom--thunder.
42099
lightning occurs when warm air hits cooler air causing friction.  lightning during a snow storm is rare because warm air is harder to come by, however it happens occaissonally when a cold front follows a period of unseasonably warm weather.
98380
.   There is something called ball lightning. It drifts slowly along and can release its energy by exploding. I read that it had been reproduced in the lab using super high voltage generators.\n.    The light from a lightning bolt travels at the speed of light but the lightning bolt travels much slower. A lightning bolt consists of ionized atoms physically moveing through the air from the cloud toward the ground and a charge comeing up from the ground to meet it. I believe the whole process takes one hundreth of a second.
157859
The first process in the generation of lightning is the forcible separation of positive and negative charge carriers within a cloud or air. The mechanism by which this happens is still the subject of research, but one widely accepted theory is the polarisation mechanism. This mechanism has two components: the first is that falling droplets of ice and rain become electrically polarised as they fall through the atmosphere's natural electric field, and the second is that colliding ice particles become charged by electrostatic induction. Once charged, by whatever mechanism, work is performed as the opposite charges are driven apart and energy is stored in the electric fields between them. The positively charged crystals tend to rise to the top, causing the cloud top to build up a positive charge, and the negatively charged crystals and hailstones drop to the middle and bottom layers of the cloud, building up a negative charge. Cloud-to-cloud lightning can appear at this point. Cloud-to-ground lightning is less common. Cumulonimbus clouds that do not produce enough ice crystals usually fail to produce enough charge separation to cause lightning.\n\nWhen sufficient negatives and positives gather in this way, and when the electric field becomes sufficiently strong, an electrical discharge occurs within the clouds or between the clouds and the ground, producing the bolt. It has been suggested by experimental evidence that these discharges are triggered by cosmic ray strikes which ionise atoms, releasing electrons that are accelerated by the electric fields, ionising other air molecules and making the air conductive by a runaway breakdown, then starting a lightning strike. During the strike, successive portions of air become conductive as the electrons and positive ions of air molecules are pulled away from each other and forced to flow in opposite directions (stepped channels called step leaders). The conductive filament grows in length. At the same time, electrical energy stored in the electric field flows radially inward into the conductive filament.\n\nWhen a charged step leader is near the ground, opposite charges appear on the ground and enhance the electric field. The electric field is higher on trees and tall buildings. If the electric field is strong enough, a discharge can initiate from the ground. This discharge starts as positive streamer and, if it develops as a positive leader, can eventually connect to the descending discharge from the cloud.\n\nLightning can also occur within the ash clouds from volcanic eruptions[1],[2], or can be caused by violent forest fires which generate sufficient dust to create a static charge.\n\nA bolt of lightning usually begins when an invisible negatively charged stepped leader stroke is sent out from the cloud. As it does so, a positively charged streamer is usually sent out from the positively charged ground or cloud. When the two leaders meet, the electric current greatly increases. The region of high current propagates back up the positive stepped leader into the cloud. This "return stroke" is the most luminous part of the strike, and is the part that is really visible. Most lightning strikes usually last about a quarter of a second. Sometimes several strokes will travel up and down the same leader strike, causing a flickering effect. This discharge rapidly superheats the leader channel, causing the air to expand rapidly and produce a shock wave heard as thunder.\n\nIt is possible for streamers to be sent out from several different objects simultaneously, with only one connecting with the leader and forming the discharge path. Photographs have been taken on which non-connected streamers are visible such as that shown on the right.\n\nThis type of lightning is known as negative lightning because of the discharge of negative charge from the cloud, and accounts for over 95% of all lightning.\n\nAn average bolt of negative lightning carries a current of 30 kiloamperes, transfe
848883
You might find this interesting,about how lightning works \nand the myths about how/what it strikes\n\nhttp://www.wvlightning.com/lmwn3.shtml
46381
Well electricity needs a path to travel in. Electricity can flow in wires, or other conductors, like a plasma, which consists of charged particles; that is, the electrons have been stripped off the atoms because they are so energetic, leaving just a seething collection of positive and negative particles (said to be "ionized"). In a lightning strike, a path of charged particles extends between the cloud and the ground, or some other object near the ground like a tree or a lightning rod or building (or sometimes between one cloud and another). The electricity in lightning follows this charged path. \n\nIf you can use a powerful laser or some other technique to form an ionized path in the air, then electricity can follow that ionized path, just like it does in lightning (or in Van de Graff generator experiments).
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Whenever there is accumulation of charge in particles in the atmosphere, equal but opposite charge is accumulated in the Earth’s surface.\n\n If an object has a blunt surface and a sharp point, charge accumulates more in the sharp point than in the blunt surface.\n\nIn a bare ground if a man stands and another man is lying on the ground near by, the probability of striking of lightning is more for the man standing than that of a man lying. Note it is a probability.\n\nWhen you are in swimming in a pool, you are the highest point near the surroundings and all the charges induced accumulate only on your body and the probability of lightning to occur is at its high value.