Question

question 8 of 15
which statement is true of magnets?

a. a magnet always has two poles.

b. electromagnets are generally weaker than permanent magnets.

c. electromagnets always have the same strength.

d. earth is a permanent magnet.

Explanation:

• Option A: By the fundamental property of magnets, every magnet, whether natural or artificial, has a north and a south pole (even if we try to break a magnet, each piece will still have two poles).
• Option B: Electromagnets can be made stronger than permanent magnets by increasing the current, number of coils, etc., so this is false.
• Option C: The strength of an electromagnet depends on factors like current, number of turns in the coil, and the core material, so it can vary, making this false.
• Option D: Earth's magnetic field is due to the movement of molten iron in its outer core (a geodynamo effect), not a permanent magnet in the traditional sense, so this is false.

Answer:

A. A magnet always has two poles.