Question

A research-level Van de Graaff generator has a 2.15 m diameter metal sphere with a charge of 5.05 mC on it. What is the potential near its surface in MV? (Assume the potential is equal to zero far away from the surface.)

Answer 1

Answer:

42.3 MV

Explanation:

d = diameter of the metal sphere = 2.15 m

r = radius of the metal sphere

diameter of the metal sphere is given as

d = 2r

2.15 = 2 r

r = 1.075 m

Q = charge on sphere = 5.05 mC = 5.05 x 10⁻³ C

Potential near the surface is given as

$V = \frac{kQ}{r}$

$V = \frac{(9\times 10^{9})(5.05\times 10^{-3})}{1.075}$

V = 4.23 x 10⁷ volts

V = 42.3 MV