The following two files show plots of electric potential as a function of distance for three charges.

The units in the graph are meters (each tick mark vertically and horizontally is 1 m), and the legend shows the value of potential at each contour.

a) (2 points) Identify the signs of all three charges (positive or negative)
b) (5 points) Determine within 25% the value of each charge in coulombs.

Word file with side view of the potentials.

Jpeg showing a top view of the voltage contours.