Electronics - Parallel Circuits - Discussion

@Meghavi.
If R4 is Shorted then there would be no resistor in the circuit. Then how will the current flow and moreover how will you apply Ohms law V=IR.

@Pankaj explained well..

Here asking for which resistor will work as open circuit and short circuit..

2.4A is going to next branch that means no current passing through R1, R2,R3 so it will work as open circuit.

R4 is only one through which current is passing ..so it behaves as short circuit.!! :)

1) 0=(I2-I1)X1K+(I2-I3)X2K
2) 0=(I3-I2)X2K+(I3-I4)X3K
3) 0=(I4-I3)X3K+I4X4K (R4=4k)

From given figure I1=I2=I3=I4=2.4A Substituing in 1,2,3

It satifies 1,2 it will be true and for 3 if R4 is shorted.

According to me, The problem is Lack of Given. The best answer is No Answer.

According to Gajjar Akash, how can current increase with resistance? and also all are resistors as the unit is ohm and as per the symbol, then where the G comes from?

Let me simplify this answer.... Look at the schematic and realize that "G" stands for conductance... So if you look at all of the branches, if either of the branches were to short other than R4, since current normally takes the easiest path, then there is no way that the current would be constant throughout every branch leading up to the final one in this circuit. So since R4 still has a the equivalent amount of the total conductance ( or current) then R4 would have to be the problematic component in this circuit.. This is a clear indication that current has taken the easiest pass at the very last branch of this circuit.

R4 is shorted because its connected between two negative potentials.

G stands for conductance only. But I don't know how D is the correct answer.

G stands for galvanometer
g stands for conductance

G is galvanometer and it measure current. 2.4 A is in the next G so no current through the R1. Similarly, no current through R2, R3 and finally whole current through R4. So R4 is short circuited and others are open circuit.