関連ワード:  value of mu not for pi    value of mu naught for pi    value of mu not 4 pi    value of mu not upon pi    value of mu not upon 2 pi    value of mu not by 2 pi    value of mu not upon 4 pi in magnetic field    value of mu not upon 4 pi in physics    value of mu not by 2 pi formula    value of mu not by 4pi