【单选题】It is known that the uniform section of the magnetic path S = 5cm.^2, the average length is L = 100cm = 1m, the relative permeability of the medium is ur = 1000, the number of turns of the iron core ...
【简答题】It is known that 5% of men and 0.25% of women are color blind. It is also known that the number of men and women in this group is equal. Now we randomly select one of them, find out the probability th...