Two heaters rated as ( P_1, V ) and ( P_2, V ) are connected in series across a dc source of V/2 volt. The power consumed by the combination will be -

Two heaters rated as $\displaystyle \left(\mathrm{P}_{1}, \mathrm{~V}\right)$ and $\displaystyle \left(\mathrm{P}_{2}, \mathrm{~V}\right)$ are connected in series across a dc source of $\displaystyle \frac{\mathrm{V}}{2}$ volt. The power consumed by the combination will be -