What causes the rumbles after a lightning strike? Here's the phenomenon of thunder, explained. Continue Reading. Share your thoughts. Related Content. Herb E-Book Projects Collection. Add to cart. Earth-Sheltered Home Blueprint. E-Plan, Windcrafter Turbine. Soap Maker's Workshop. The New Livestock Farmer. Aquaponic Gardening. Re-Connect in Person with Farmers and Foodies. This is for Mustard Lovers!
Solar on Schools. If you have ever played with magnets, you will know that the positive side of a magnet is attracted to the negative side of another magnet — but it pushes away the positive side of another magnet.
Opposites attract each other: those with the same charge that is, positive or negative push each other away. The same thing happens with the negatively charged water droplets near the bottom of the thunder cloud.
All the negative bits that collect near the bottom of the cloud are called electrons. Positive bits known as particles start to collect under the thunder cloud because they are attracted by the electrons near the bottom of the cloud.
The attraction of positive and negative bits is strong, so the electrons in the cloud start to make jagged fingers reaching down to the earth. As soon as the negative bits from the cloud connect with the positive bits from the earth, a huge current made of all those electrons flows to the earth — and that is the lightning flash you see.
The lightning flash heats the air around it so quickly that the air expands very fast. When you heat something, it gets bigger — it expands. The air around the lightning flash expands so fast that it makes a shock wave in the air. Since you see lightning immediately and it takes the sound of thunder about 5 seconds to travel a mile, you can calculate the distance between you and the lightning.
Keep in mind that you should be in a safe place while counting. Remember, if you can hear thunder, chances are that you're within striking distance of the storm. You don't want to get struck by the next flash of lightning. To learn more, see Acknowledgements and References or return to Contents page.
The audiovisual spectacle of thunder and lightning is a combination of the dynamics of the vibration of air molecules and their disturbance by electrical forces. It is an awesome show--and one that reminds all of us of the powers of nature and our own insignificance in relation to them.
Answer originally posted January 17, Sign up for our email newsletter. Already a subscriber? Sign in. Thanks for reading Scientific American.
0コメント