Question

An electrical appliance of $R\Omega$ resistance draws a current ‘I’ for time ‘t’. It is connected across a battery which offers a potential difference V. The energy consumed by the appliance is given by:

• A. $VIt$
• B. $I^{2}Rt$
• C. $\frac{V^2}{R}t$
• D. All of the above

Answer 1

The correct option is D

All of the above

Energy dissipated = work done $=Power\times time$
Work done for a charge q to move in a potential difference $Visq\times V$
Power = Work done per unit time $=\frac{q\times V}{t}$
$\therefore Power=VI(I=\frac{q}{t})$
$\therefore$ Energy dissipated = VIt (Power = VI)
Energy dissipated $=I^{2}Rt(V=IR)$
Energy dissipated $=\frac{V^2}{R}t(I=\frac{V}{R})$