Turn on your desk lamp. Pick up the cord, with your thumb and index finger spanning the width of the cord.
(a) Compute an order-of-magnitude estimate for the current in your hand. You may assume that at a typical instant the conductor inside the lamp cord next to your thumb is at potential ~102 V and that the conductor next to your index finger is at ground potential (0 V). The resistance of your hand depends strongly on the thickness and the moisture content of the outer layers of your skin. Assume that the resistance of your hand between fingertip and thumb tip is ~104 Ω. You may model the cord as having rubber insulation. State the other quantities you measure or estimate and their values. Explain your reasoning.
(b) Suppose that your body is isolated from any other charges or currents. In order-of-magnitude terms describe the potential of your thumb where it contacts the cord, and the potential of your finger where it touches the cord.