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Now if α, β, γ be the components of the magnetic induction at the point (x, y, z),

Hence we see, by symmetry, that if the sphere move with velocity q parallel to the axis of y, the corresponding values would be

and if it moved with velocity r parallel to the axis of z, the corresponding values would be

Hence, if p, q, r be the components of the velocity of the centre of the sphere parallel to the axes of x, y, z respectively, the components of magnetic induction are