For the resistance network shown in the figure, choose the correct options (s)

Options

A. (i),(ii)
B. (i),(ii),(iii)
C. (i),(ii),(iv)
D. (ii),(iii),(iv)

Answer

C

Explanation

Current `I_1` is divided into `I_2` and `I_3` at `A`
At `B, I_2` and `I_3` enters at `B`
It shows that `P` and `Q, S` and `T` are at same potential, no current flows in `PQ` and `ST`.

`I_2 = (12)/(6) = 2 A, I_3 = (12)/(12) = 1A`
`I_1= I_2 + I_3 = 3 A`
`V_A - V_S = I_2(2 + 2) = 2 xx 4 = 8 V rArr V_S = V_A - 8`
`V_A - V_Q = I_3 xx 4 = 3 xx 4 = 12 V rArr V_Q = V_A - 12`
`V_Q lt V_S`.