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13 Cards in this Set
- Front
- Back
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WHAT IS LIGHTNING?
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a discharge of electricity, a giant spark, that occurs in mature thunderstorms
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DESCRIBE HOW THE ANNUAL FREQUENCY OF LIGHTNING VARIES ACROSS THE US.
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Florida is the overall leader, its shape ocean-land heat contrast and air circulations that trigger storms year-round. The High Plains and foothills of the Rocky Mountains receive intense summer lightning due to elevated heating, moisture from the Gulf of Mexico, and their high altitude. (Even small clouds over the Rockies are cold enough to carry the ice crystals crucial to lightning formation).
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WHERE IS LIGHTINING MOST COMMON IN THE US? WHY?
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Florida is the overall leader: its peninsular shape causes ocean-land heat contrast and air circulations that trigger storms year-round.
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EXPLAIN HOW A CLOUD-TO-GROUND LIGHTNING STROKE DEVELOPS.
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Begins within the cloud when the localized electric potential gradient exceeds 3 million volts per meter along a path perhaps 50 meters long. This situation causes a discharge of electrons to rush toward the ground in a series of steps
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WHAT IS LIGHTNING?
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a discharge of electricity, a giant spark, that occurs in mature thunderstorms
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|
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DESCRIBE HOW THE ANNUAL FREQUENCY OF LIGHTNING VARIES ACROSS THE US.
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Florida is the overall leader, its shape ocean-land heat contrast and air circulations that trigger storms year-round. The High Plains and foothills of the Rocky Mountains receive intense summer lightning due to elevated heating, moisture from the Gulf of Mexico, and their high altitude. (Even small clouds over the Rockies are cold enough to carry the ice crystals crucial to lightning formation).
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WHERE IS LIGHTINING MOST COMMON IN THE US? WHY?
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Florida is the overall leader: its peninsular shape causes ocean-land heat contrast and air circulations that trigger storms year-round.
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EXPLAIN HOW A CLOUD-TO-GROUND LIGHTNING STROKE DEVELOPS.
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Begins within the cloud when the localized electric potential gradient exceeds 3 million volts per meter along a path perhaps 50 meters long. This situation causes a discharge of electrons to rush toward the ground in a series of steps
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HOW IS THUNDER PRODUCED?
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Lightning stike can heat the air it strikes to an incredible 54,ooo degrees F, which is five times hotter than the sun. This extreme heating causes the air to expand explosively, thus initiating a shock wave that becomes a booming sound wave-called thunder.
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IF YOU SEE LIGHTNING AND TEN SECONDS LATER YOU HEAR THUNDER, HOW FAR AWAY IS THE LIGHTNING STROKE?
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-2 miles
-five seconds per mile |
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WHY DOES SOME THUNDER SOUND LIKE A SHARP CRACK OR A LOUD BANG?
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When the lightning stroke is close thunder sounds like a clap or a crack followed immediately by a loud bang. When it's far it rumbles.
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WHAT IS HAPPENING WHEN YOU SEEN LIGHTNING BUT DO NOT HEAR THUNDER AT ALL?
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The atmosphere refracts (bends) and attenuates that sound waves, making them inaudible.
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WHY IS IT UNWISE TO SEEK SHELTER?
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because a positive charge tends to concentrate in upward projecting objects, the upward return stroke that meets the stepped leader is most likely to originate from such objects.
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