8. Imagine for a minute that the moon is held in its orbit about the Earth by electrical forces rather than

by gravitation. What is the necessary electrical charge -Q that would be on the Earth and +Q that

would be on the moon to hold the moon in a circular orbit of 27.3 days? The Earth-moon distance is

384,000 km and the mass of the moon is 7.35 x 1022 kg.