GEOLOGY

Detailed explanation-1: -Explanation: Juanita sticks a nail to the end of a bar magnet. She then sticks a second nail to the first, then another to that one, and so on. When she gets to the seventh nail, it falls off the sixth nail.

Detailed explanation-2: -Magnets have two poles; the field lines spread out from the north pole and circle back around to the south pole.

Detailed explanation-3: -It is because the magnet induces magnetism in the iron nail that gets attracted by the magnet and grips to it. The magnetized nail tends to magnetize other nails around it through the process of magnetic induction and thereby attracts it.

Detailed explanation-4: -In the first part of the question, if we vary the distance between magnet and nails, then the force of attraction between the nails and the magnet changes farther the distance between the magnet and the nail less magnetism is seen and more close.

Detailed explanation-5: -The nail will stick to the bar magnet because it will become magnetized. The presence of the nearby north pole rearranges the magnetic domains inside the steel so that their south poles all point toward the north pole of the permanent magnet. As a result, the other end of the nail becomes a north pole.