(a) A lightbulb has a resistance of 255 (1 when operating with a potential difference of 155 V across it. What is the current in the lightbulb (in mA)? 1000 x The resistance of a lightbulb varies for different values of the applied voltage, but at any particular voltage it has a fixed value as in this problem. What is the equation relating voltage to current? mA (b) what If? What would be the current in the lightbulb (in mA) if it were used in Japan, where the potential difference across it would be 100 V? :m