Charge Q = 8.00 μC is distributed uniformly over the volume of an insulating sphere that has radius R = 13.0 cm. A small sphere with charge q=+ 3.00 μC and mass 6.00×10^−5kg is projected toward the center of the large sphere from an initial large distance. The large sphere is held at a fixed position and the small sphere can be treated as a point charge.

Rrequired:
What minimum speed must the small sphere have in order to come within 9.00 cm of the surface of the large sphere?