A Van de Graaff generator is used to demonstrate the effects of high potential. The device has a radius of 86.0 cm and stands in air. What is its maximum potential? (Note: An electric field of 3 × 106 Vm is sufficiently large to cause sparking in air.)
How much charge does the dome hold at its maximum potential?
Electric Potential = (1/4*pi*e0) * q / r
The Attempt at a Solution
I already found the maximum potential to be 2.58 * 10^6 V.
For the charge: I substituted 2.58 * 10^6 V into the equation along with the radius.
2.58 * 10^6 V * 4 * pi * e0 * 0.86 m = q
q = 0.000247 C
This wasn't the correct answer.