Potential of Point-Charges: A sphere with radius 2.0 mm carries a +2.0 ?C charge. What is the potential difference, VB - VA, between point B, which is 4.0 m from the center of the sphere, and point A, which is 6.0 m from the center of the sphere? (k = 1/4??0 = 9.0 × 109 N ? m2/C2)
A. 1500 V
B. -1500 V
C. 170 V
D. -0.63 V
Answer: A
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