What is near the Geographic North Pole, a Magnetic North or a Magnetic South? We know two things:
2. We know that like poles repel each other and unlike poles attract each other. Therefore: |
CORRECTED: THE NORTH MAGNETIC POLE OF THE EARTH IS NOT IN THE NORTH
Opposite poles attract. If we hold two bar magnets near each other, the "N" pole of one magnet is attracted by the "S" pole of another. If we suspend a bar magnet by a thread, the "N" pole of that
magnet will point... toward the Earth's north! Something is wrong here. Shouldn't the "N" pole of a magnet point towards the "S" of the Earth? Alike poles should repel, not attract. Either the
"N" and "S" printed on all bar magnets is reversed, or the "N" and "S" on the Earth is backwards. Which is it? This problem has a simple solution. Physicists define "N-type"
magnetic poles as being the north-pointing ends of compasses and magnets. This definition is built into all of modern science and engineering and is part of Maxwell's equations. Wind an electromagnet coil, see which end points
towards the Earth's north pole, and that end is the "N pole" of the electromagnet. And this means that the magnetic pole found deep inside the northern hemisphere of the Earth is a south-type magnetic pole. The Earth's
northern magnetic pole is an S! It has to be this way, otherwise it would not attract the N-pole of a compass. This is a long-standing but arbitrary physical standard, much the same as defining electrons as being negative. Like
it or not, we are stuck with negative electrons, with seconds which last about 1/100,000 of a day, with backwards Earth poles, with centimeters which are about as wide as a small finger, etc. |
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