1. Place four charges, two positive and two negative, at four random points on a grid. Click on "Values." Drag the voltage sensor in the vicinity of the charges and click on the pencil icon. A line will appear labeled by a number. a. Move the sensor in a way such that the intersection of crosshairs remains on the line. Does the number on the sensor change? What is the physical meaning of this line?
b. Move the sensor to a different spot and click "plot" again. In this manner, create 8 to 10 lines.
c. Take an electric field sensor and move it on an equipotential line. What can you say about the way magnitude and direction of the electric field changes as the sensor travels around the line?
d. Place a few electric field sensors in a few points between the equipotential lines. Where do the electric field vectors point in terms of increase and decrease of the values on the equipotential lines?

2. Remove the charges and lace a positive charge in the center of the grid. Draw five equipotential circles with the potentials of 10 Volts, 8 Volts, 6 Volts, 4 Volts and 2 Volts. (It might be hard to get the precise values but try to get as close as you can). Take an electric field sensor and move it in a straight line, crossing the equipotential lines. Describe the relationship between the distance between the equipotential lines and the strength of the electric field.

Conclusions:

Use the observations above and the concept of work to describe and explain

a. the relative orientation between the equipotential lines and field lines
b. the relationship between the direction of the electric field and increase or decrease in potential
c. the relationship between the magnitude of the electric field and the distance between the pairs of lines with the equal potential difference