Question

What is the total current supplied by the battery to the circuit shown in the adjoing figure ?
(A) 2 A
(B) 4 A
(C) 6 A
(D) 9 A

Answer 1

if we arrange it , we will get circuit as shown in figure.

see figure, 6 ohm and 2 ohm are in parallel
so, resistance CB, R' = 6 × 2/(6 + 2) = 1.5 ohm

R' and 1.5 ohm are in series combination so,
R" = R' + 1.5 ohm = 1.5 ohm + 1.5 ohm
R" = 3 ohm

Finally, R" and 3ohm are in parallel combination so, Req = R" × 3ohm/(R" + 3ohm)
Req = 3 × 3/(3 + 3) = 1.5 ohm

now use Ohm's law, V = iReq
so, i = V/Req = 9/1.5 = 6A

hence option (C) is correct