An emf self-induced in a solenoid of inductance L changes in time as E=E_0e^(-kt) Find the total charge that passes through the solenoid, if the charge is finite. (Use E_0 for 0, k, and L as necessary.) Now I know that the induced emf is E_L=-L(dI/dt) I'm having a hard time on this problem since I'm looking for the charge, and not for the current which I believe I have to determine in the first place. I'm not sure how to exactly find di/dt and then relate it to the charge. Could anyone assist with this please?