Question

For the initially relaxed circuit shown below, KVL with switch in the closed position gives a certain equation. The Laplace of this equation will have the right hand side (RHS) as

(a) Vs

(b) (Vs x s)/RC

(c) Vs/s

(d) RC/s

The question was posed to me in homework.

My question is taken from Diode Circuits-2 in division Diode Circuits of Power Electronics

Answer 1

Right choice is (c) Vs/s

For explanation I would say: When switch is closed,

Ldi/dt + 1/C ∫ idt  =  Vs

Laplace of the above gives,

                                L[sI(s)] + 1/C [I(s)/s] = Vs/s.