EARTH SCIENCE
MAGNETISM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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All metals are magnetic
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All magnets produce a magnetic field with field lines that are stronger at the poles.
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You can test if a metallic object is a magnet by seeing if it is attracted to another known magnet
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A compass works because the Earth’s iron core produces a giant magnetic field
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Electromagnets cannot be made stronger
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Detailed explanation-1: -Compass needles line up with magnetic fields. Since Earth is a magnet, a compass will normally line up with Earth’s magnetic field. Because opposite magnetic poles attract, the magnetic north pole of the compass points toward the magnetic south pole of the Earth.
Detailed explanation-2: -Yes, Earth is basically a giant magnet! An English scientist William Gilbert explained about 400 years ago, Earth behaves like a giant bar magnet with one pole up in the Arctic (near the north pole) and another pole down in Antarctica (near the south pole).
Detailed explanation-3: -The crust of the Earth has some permanent magnetization, and the Earth’s core generates its own magnetic field, sustaining the main part of the field we measure at the surface. So we could say that the Earth is, therefore, a “magnet."
Detailed explanation-4: -The Earth’s outer core is in a state of turbulent convection as the result of radioactive heating and chemical differentiation. This sets up a process that is a bit like a naturally occurring electrical generator, where the convective kinetic energy is converted to electrical and magnetic energy.