Consider the circuit shown in the figure.


The value of the resistance X for which the thermal power generated in it is practically independent of small variation of its resistance is

Consider the circuit shown in the figure where all the resistances are of magnitude 1 k$$\Omega$$. If the current in the extreme right resistance X is 1 mA, the potential difference between A and B is

Consider the circuit given here. The potential difference V_BC between the points B and C is

Two wires of same radius having lengths l₁ and l₂ and resistivities $${{\rho _1}}$$ and $${{\rho _2}}$$ are connected in series. The equivalent resistivity will be