Now remove the three positive charges (drag them back to their storage box). Place a single 1 nC positive charge and a s

[answerhappygod]

Now remove the three positive charges (drag them back to their
storage box). Place a single 1 nC positive charge and a single 1 nC
negative charge 3 meters apart. Drag the potential meter slowly
from the positive charge to the negative charge, watching the
voltage reading as it changes. Describe how the voltage varies as
you go from one charge to the other. (You can also visualize this
by checking the Voltage box.) a. What is the voltage halfway
between the charges? b. Now, making sure that the charges are
precisely lined up with the grid, carefully choose a random
location on the line between the two charges, and carefully measure
the distance from each of the charges using the tape measure. c.
Using the charge and distance values calculate the value of the
potential at your location. d. Now use the blue potential meter to
measure the potential at that location. Do your calculated and
measured values agree?