47. A solid nonconducting sphere of radius R carries a total charge Q distributed uniformly throughout its volume. At a distance r＜R from the center, the magnitude of the electric field is E. If the radius of the sphere were doubled to 2R while keeping the total charge Q distributed uniformly and the point r the same, what would be the new magnitude of the electric field?
(A) E
(B) E/2
(C) E/4
(D) E/6
(E) E/8

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