Physics-ch-30/exercise 49
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Question 49





Q49:The magnetic moment of the Earth is approximately A?m2. Imagine that the planetary mag- netic field were caused by the complete magnetiza- tion of a huge iron deposit with density kg/m3 and approximately iron atoms/m3.
(a) How many unpaired electrons, each with a mag- netic moment of A ? m2, would participate?
(b) At two unpaired electrons per iron atom, how many kilograms of iron would be present in the deposit?
pi =
g =