Imagine for a minute that the Moon is held in its orbit about the Earth by electrical forces rather than by gravitation. What electrical charges -Q on the Earth and +Q on the Moon are necessary to hold the Moon in a circular orbit with a period of 27.3 days? The Earth-Moon distance is 384 000 km and the mass of the Moon is 7.35 1022 kg.
Question 2
An alpha particle (charge = +2e) is sent at high speed toward a gold nucleus (charge +79e). What is the electrical force acting on the alpha particle when it is at a distance of 2 10-14 m away from the gold nucleus? (e = 1.6 10-19 C)
The Sun as it appears from the surface of Earth during the middle of the day
Size comparison of Earth and Mars.
The Moon’s Interior
How Orbital Eccentricity Changes the Amount of Solar Radiation Earth Receives
Earth’s Spheres
Escape Speed from Earth