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What is
thunder and lightning?
Thunder is the sound lightning makes. That sounds
pretty easy, but why would lightning make a sound in the first place.
Any and all sounds you hear come from vibrations. These vibrations
travel though the air until they reach your ear. So for lightning to
make a sound, it must cause some vibrations.
Lightning is a huge release of electricity. Within
a thundercloud, many tiny bits of frozen raindrops rub together as they
move around in the air. All of this rubbing creates an electric charge.
This is the same process as when you rub your sock covered feet on the
carpet and “shock” someone with a touch.
When electricity hits the air, the air starts to
vibrate. Lightning is also extremely hot and heats up the air around it.
Hot air gets bigger and expands. Since lightning is very hot, the air
around it gets bigger very quickly and pushes against air particles
causing more vibrations. These vibrations cause sound. In this case,
it’s thunder.
What causes
our seasons?
In West Virginia, we have four seasons during the
year: spring, summer, fall and winter. These four seasons come from the
tilt of the Earth. In reality, the North Pole and South Pole are not
directly overtop one another. The Earth is tilted at 23 degrees.
The season we experience depends on whether we are
tilted toward or away from the Sun. In the spring, the northern half of
the Earth is tilted toward the Sun. The days get longer and warmer as
the year progresses. By the middle of summer, the rays of the Sun are
shining directly on the northern hemisphere. Then, as the Earth begins
to tilt away from the Sun, the days get shorter and cooler. So, in the
middle of winter, the rays of the sun are shining directly on the
southern hemisphere.
You can demonstrate this concept using a basketball
and a flashlight. Have someone hold the basketball at a slight angle
toward the flashlight and shine the flashlight at the “equator.” More
direct light hits the northern hemisphere that is tilted toward the
flashlight, while the southern hemisphere still receives light, just not
direct light.
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