Two conductors have the same resistances at $$0^{\circ} \mathrm{C}$$ but their temperature coefficients of resistance are $$\alpha_1$$ and $$\alpha_2$$. The respective temperature coefficients for their series and parallel combinations are :
When a potential difference $$V$$ is applied across a wire of resistance $$R$$, it dissipates energy at a rate $$W$$. If the wire is cut into two halves and these halves are connected mutually parallel across the same supply, the energy dissipation rate will become:
A potential divider circuit is shown in figure. The output voltage V$$_0$$ is :
An electric toaster has resistance of $$60 \Omega$$ at room temperature $$\left(27^{\circ} \mathrm{C}\right)$$. The toaster is connected to a $$220 \mathrm{~V}$$ supply. If the current flowing through it reaches $$2.75 \mathrm{~A}$$, the temperature attained by toaster is around : ( if $$\alpha=2 \times 10^{-4}$$/$$^\circ \mathrm{C}$$)