Do not use electric equipment like computers and appliances during a storm. Stay away from windows and doors and stay off porches. Call or send for help immediately. The injured person does not carry an electrical charge, so it is okay to touch them. Lightning What is lightning? Lightning is a bright flash of electricity produced by a thunderstorm. All thunderstorms produce lightning and are very dangerous.
If you hear the sound of thunder, then you are in danger from lightning. Lightning kills and injures more people each year than hurricanes or tornadoes; between 75 to people. What causes lightning?
Lightning is an electric current. Within a thundercloud way up in the sky, many small bits of ice frozen raindrops bump into each other as they move around in the air. All of those collisions create an electric charge. After a while, the whole cloud fills up with electrical charges. The positive charges or protons form at the top of the cloud and the negative charges or electrons form at the bottom of the cloud. Since opposites attract, that causes a positive charge to build up on the ground beneath the cloud.
The grounds electrical charge concentrates around anything that sticks up, such as mountains, people, or single trees. The charge coming up from these points eventually connects with a charge reaching down from the clouds and - zap - lightning strikes! Have you ever rubbed your feet across carpet and then touched a metal door handle?
If so, then you know that you can get shocked! Lightning works in the same way. Click Here to see where lightning is currently striking across the U. How hot is lightning? Lightning is approximately 54, degrees Fahrenheit. That is six times hotter than the surface of the sun! What color is lightning? Lightning seems to be clear or a white-yellow color, but it really depends on the background.
What causes thunder? Thunder is caused by lightning. When a lightning bolt travels from the cloud to the ground it actually opens up a little hole in the air, called a channel.
Once then light is gone the air collapses back in and creates a sound wave that we hear as thunder. The reason we see lightning before we hear thunder is because light travels faster than sound! Each of these segments is about feet 46 meters long. When the lowermost step comes within feet 46 meters of a positively charged object, it is met by a climbing surge of positive electricity, called a streamer, which can rise up through a building, a tree, or even a person.
When the two connect, an electrical current flows as negative charges fly down the channel towards earth and a visible flash of lightning streaks upward at some ,, mph ,, kph , transferring electricity as lightning in the process. Some types of lightning, including the most common types, never leave the clouds but travel between differently charged areas within or between clouds.
Other rare forms can be sparked by extreme forest fires, volcanic eruptions, and snowstorms. Ball lightning, a small, charged sphere that floats, glows, and bounces along oblivious to the laws of gravity or physics, still puzzles scientists. About one to 20 cloud-to-ground lightning bolts is "positive lightning," a type that originates in the positively charged tops of stormclouds. These strikes reverse the charge flow of typical lightning bolts and are far stronger and more destructive.
Positive lightning can stretch across the sky and strike "out of the blue" more than 10 miles from the storm cloud where it was born. About 2, people are killed worldwide by lightning each year. Hundreds more survive strikes but suffer from a variety of lasting symptoms, including memory loss, dizziness, weakness, numbness, and other life-altering ailments.
Strikes can cause cardiac arrest and severe burns, but 9 of every 10 people survive. The average American has about a 1 in 5, chance of being struck by lightning during a lifetime. Lightning's extreme heat will vaporize the water inside a tree, creating steam that may blow the tree apart.
Cars are havens from lightning—but not for the reason that most believe. Tires conduct current, as do metal frames that carry a charge harmlessly to the ground. When the stepped leader and the positive charge meet, a strong electric current carries positive charge up into the cloud. This electric current is known as the return stroke. We see it as the bright flash of a lightning bolt. Thunder and lightning occur at roughly the same time although you see the flash of lightning before you hear the thunder.
This is because light travels much faster than sound. Lightning happens when the negative charges electrons in the bottom of the cloud are attracted to the positive charges protons in the ground.
When lightning is made the same thing happens, but on a much bigger scale. When the ground is hot, it heats the air above it. This warm air rises. As the air rises, water vapour cools and forms a cloud. When air continues to rise, the cloud gets bigger and bigger. In the tops of the clouds, temperature is below freezing and the water vapour turns into ice. Now, the cloud becomes a thundercloud. Lots of small bits of ice bump into each other as they move around.
All these collisions cause a build up of electrical charge. Eventually, the whole cloud fills up with electrical charges. Lighter, positively charged particles form at the top of the cloud.
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