Hello; I just wanted to clarify whether I am using this formula correctly. By definition, current is the rate of flow of charge. In other words, its how much charge flows per second. One amp (1 A) is equal to one coulomb per second (1 C/s). Charge and current are related by the equation: I = ΔQ/ΔT. 1) A battery supplies 10 C over a period of 50 seconds. What is the current? My answer: Given the formula above, I = 10 coulombs / 50 seconds = 0.2 A. Is this correct? 2) Another battery is connected for 2 minutes and provided a current of 0.4 A. How much charge flowed? My answer; 0.4 = Q/120 Q = 0.4*120 = 48 C 3) A car battery has a capacity of 24 Ah (amp hours). If it provides a current of 48A how long can it be used for? How much charge (in coulombs) does it contain? My answer: Not completely sure about this question, but I think that the car battery can be used for 2 hours. As for the latter question, I don't understand... how do I convert from amp hours to amps? Thanks.