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The reason the north pole of a bar magnet free to rotate points north is because?

a. the north geographic pole of the earth is the earth's magnetic north pole. b. The south geographic pole of the earth is the earth's magnetic south pole. c. there is a net accumulation of negative magnetic charge at the earth's south geographic pole. d. There is a net accumulation of positive magnetic charge at the earth's north geographic pole. e. The north geographic pole of the earth is the earth's magnetic south pole.

Public Comments

1. So you (should) know that the north pole of a magnet is attracted to the south pole of other magnets. Also, there's no magnetic charge, so it's E.
2. The north pole of a free bar magnet does NOT rotate to point at the north pole. If you look at a compass, the pointer (our freely rotating bar magnet) is labeled North at one and and South at the other. These labels do not reflect the polarity of the magnet, but rather the direction that the magnet is pointing. So, the SOUTH pole of the freely rotating bar magnet points to the NORTH. North poles attract South poles and vise versa. Like poles however, repel. A quick fun fact, the North pole of a magnet is where magnetic field lines leave or 'flow' out of a magnetized object and the South pole is where they reenter. These field lines do not actually exist, but are a abstract construct to describe the 'shape' of a magnetic field and it's influence. On the answers you gave: Magnetic north is definitely located NEAR the geographic north pole. Magnetic south is located NEAR the geographic south pole. Note that the magnetic south pole is NOT at the geographic north pole and the magnetic north pole is not located at the geographic south pole. The answer to this question is not in your list as it as the question is stated. None of the above.
3. E . The earth's geographic north pole is actually earth's magnetic south pole. http://adventure.howstuffworks.com/outdoor-activities/hiking/compass1.htm The polarity of the earth's magnetic field is constantly fluctuating in strength and has actually reversed many times since the earth was created, with the next magnetic reversal actually due in about 1500 years. Scientists found this out by studying the positions of lodestones (magnetized rocks) around our planet. When a lodestone is formed (like by a volcano spewing lava that cools), it should be aligned with the magnetic field of the earth. And, when the rock is unearthed, it should be pointing in the approximately correct direction (some tectonic activity may have changed its position). But, geologists have found many lodestones pointing in the opposite direction that they should. And, by carbon dating these rocks, geologists have found that rocks from certain time periods tend to be found positioned in the opposite polarity that they should be for the current magnetic alignment of the earth. So, they infer that the polarity of the earth's magnetic field was reversed during these times.
4. e. The north geographic pole of the earth is the earth's magnetic south pole.