Question

The intensity of the earth's magnetic field _____

A) has gotten weaker over time
B) has completely disappeared is greater today than in the past
C) is the same as it was in the past
D) None of these

Answer 1

The Earth's magnetic field has weakened over time, is strongest at the poles, and is generally parallel to the ground only at the magnetic equator.

Step-by-step explanation:

The intensity of the Earth's magnetic field has gotten weaker over time. This field is not parallel to the ground at all locations; it is generally parallel at the magnetic equator. The strength of the Earth's magnetic field is not the same at all locations; it is the greatest at the poles and weakest at the equator. Magnetic fields, like the one around a bar magnet, decrease in strength with distance. This behavior is consistent with our experience with magnets. As per modern technology, magnetic field strengths of 0.500 T are easily produced with permanent magnets, which is much greater than the Earth's field strength of approximately 5x10-5 T at its surface.