P and Q are magnetized to the same level by applying two different currents Ip and Iq, such that Iq > Ip. Q requires greater magnetizing power, since its domains are more difficult to align; P is easier to magnetize, since its domains are more easily aligned.
OR
When magnetizing current is increased, the dipoles align more and more until magnetic saturation is attained where the magnetization becomes maximum and remains constant. Substance P requires less current than Q to attain saturation. This means that P is easily magnetized and also easily demagnetise- than Q. This also means that P can form temporary magnet while Q can for permanent magnet thus P is soft and Q is hard magnetic materials.
johnmulu answered the question on April 18, 2017 at 09:14
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