Spheres of Charge: a Non-Conducting Sphere of Radius R =

Multiple Choice

Spheres of charge: A non-conducting sphere of radius R = 7.0 cm carries a charge Q = 4.0 mC distributed uniformly throughout its volume. At what distance, measured from the center of the sphere, does the electric field reach a value equal to half its maximum value?

A) 3.5 cm only
B) 4.9 cm only
C) 3.5 cm and 9.9 cm
D) 3.5 cm and 4.9 cm
E) 9.9 cm only