Abstract: In this paper, we calculate the electromotive forces produced by various regions of magnetic field. First, we discuss the electromotive forces in the case of finite long straight conductor. We calculate the electromotive forces for the circular, rectangular and triangular shapes of magnetic field and get analytic results. We find that the results depend on the shapes of the magnetic field and the size of the conductor. Second, we discuss the electromo- tive forces for the case of infinite conductor. In this case, we prove that the electromotive forces only depend on the cross-sectional area of magnetic field. The results are independent of the shapes of magnetic field and the distance from the magnetic to the conductor.

Key words: electromagnetic induction, motional electromotive force, induced electromotive force