Answer
See answers.
Work Step by Step
As shown in Figure 20-42a, in the unmagnetized nail and paper clip, the magnetic domains are initially pointing in random directions.
Suppose the north pole of a strong magnet now touches the nail. Some of the domains in the nail rotate slightly to orient their south poles closer to the contact point. This partial alignment of domains causes the nail’s magnetic domains to resemble those in Figure 20-42b, i.e., the part of the nail near the contact point becomes the south pole of a weak magnet. The nail, which has now become a weak magnet, can attract an unmagnetized paper clip (as explained in Question 24).
