1 DC power supply (0-15V), 1 multimeter, 4 metallic surface, connection equipment and cables, 1 conductive surface, a set of graph paper.Technical Information
When there is a potential difference between any two points on a conductive medium, an electric field occurs and the charge (q) feels an electric force. This force is given by F = qE where electric field is related the gradient of potential E = -∇ V. When potential does not change along a curve, this curve is called equipotential line. These equipotential lines and electric field lines are perpendicular to each other. The experiment is done by first fixing circular or straight metals by screwing tightly. Then a DC voltage of 10 V is applied between these metals. This causes charge (so that potential) distribution on the conductive surface. The voltage reduces from high voltage to low voltage side. This can easily be measured by just touching the tip of the multimeter probe.The same voltage values are found by changing the location of the probe tip and this point is marked on a graph paper. By connecting these points equipotential lines of 8, 6, 4, 2 V are drawn. From these curves, the perpendicular electric field lines are obtained.