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Thames & Kosmos Magnetic Science Experiment Manual page 37

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EARTH'S MAGNETIC FIELD
For centuries, it was a complete mystery why a magnetic needle
pointed to the north or south. Scientists rightly asked what the
Today we know that Earth acts as if there were a giant bar magnet
hidden inside it. But Earth's magnetic poles don't exactly match the
rotational poles. Instead, they are a few thousand kilometers away. Between these
magnetic poles, there is a powerful magnetic field stretching across the entire globe.
This is what your magnets and all magnetic compasses react to. Earth's magnetic field
isn't actually produced by a permanent magnet, but by enormous electric currents
circulating deep beneath the surface in its metallic core.
MAGNETIC MOUNTAINS C
particularly strong magnetic field at Earth's magnetic poles. And there's
nothing very unusual about the landscape there. The supposed
magnetic mountains — in the Middle Ages, people believed in the
existence of a magnetic mountain that could pull the iron nails out of
ships that passed by it — belong to the realm of fairy tales. What is
interesting is that the magnetic field's lines of force enter the magnetic
poles in a vertical direction, so the needle of an appropriately designed
compass will point straight down.
Magnetic Force and Magnetic Fields |
rotation of Earth might have to do with magnetism. Were there,
for example, gigantic magnetic mountains at Earth's poles? Or
might the North Star, which could be seen above the North Pole,
be responsible?
CHECK IT OUT
In fact, you can't detect any
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