Question

The current in the inductor of the circuit(see attachment)is I=1-e^(-t).What is the input current ?

Answer 1

isnt it just KCL

Answer 2

current in capacitor = C dv/dt

Answer 3

consider the far left branch,

you know that current through it is 1-e^-t

now, V = L di/dt for an inductor

Answer 4

so the voltage drop acorss inductor is e^-t

and by ohms you know the voltage across resistor is 1- e^-t

Answer 5

now the sum of these voltage drops must equal to voltage drop across capacitor, because they are in parallel

Answer 6

so the voltage across the capacitor is 1

therefore capacitor current = C dv/dt = 0 because V is constant.

so that means that the input current is 1-e^-t


mmm hope I havent done anything wrong

Answer 7

seems bit strange