A.) Two charges attract each other with a force of 1.0 N. What will be the force if the distance between them is reduced to one-ninth of its original value?
B.) Suppose a single electron orbits about a nucleus containing two protons (+2e), as would be the case for a helium atom from which one of the naturally occuring electrons is removed. The radius of the orbit is 4.78 × 10-11 m. Determine the magnitude of the electron's centripetal acceleration.