Using charging by contact, design a semi-quantitative experiment (taking a few data points) to determine how the Electrostatic Force varies with charge, without having to directly measure the charge. It will only be necessary to vary the charge on one of the spheres - think of how you can halve the charge on sphere, and continually do so. There is a third copper sphere on your lab table which is identical to the other two [except for the handles) - this can carry as much charge as they. Again, describe your experiment in detail, include your data and also your calculations. (25 pts)