In the following circuits, (Fig. 3.38), heat produced in the resistor or combination of resistors connected to a `12 V` battery will be :

Options

A. same in all the cases
B. minimum in case (i)
C. maximum in case (ii)
D. maximum in case (iii)

Answer

D

Explanation

In case (i), `R_1 = 2 Omega`, in case (ii), `R_2 = 2 Omega + 2 Omega = 4 Omega` and in case (iii), `R_3 = (2 Omega)/(2) = 1 Omega`.
Since `P = (V^2)/( R)`, heat produced is maximum in case (iii).