3. As astronauts consider how to better study Excalibur, they reflect on some of the probes they have used in our own solar system. They recall a probe that they released from a spacecraft onto the moon. The probe sends signals to a transmitter on the spacecraft. Assuming that the probe and transmitter are 10m apart and they have no initial charge, what negative charge must be transferred to the probe to create an attractive force between them of 200N? (Show your work) (5 points)
4. Using your knowledge of Newton's Universal Law of Gravitation and Coulomb's Law, compare and contrast them. How are they similar? How are they different? (5 points)
