Exercise 10.2 Suppose the rails in Figure 10.5a have a resistance per unit length r [Ω/m] each. The bar is perfectly
conducting. Calculate the current in the resistor R at a time t if the bar starts at t ¼ 0 at x ¼ 0 (x ¼ 0 is at the location of
R) and moves at constant speed v in the negative x direction.