Question

Write one expression for the electrical energy in terms of its potential difference, resistance and time.

Answer 1

1. If a certain amount of power is dissipated for a given time, then energy is dissipated.
2. Energy is defined as the ability or capacity to do some work.
3. Energy is measured in Joules and by including time ($t$) in the power formulae, the energy dissipated by a component or circuit can be calculated.

Step 1: Calculating Energy dissipated

Energy dissipated , $E=P\times t=VIt,becauseweknowthatpowerP=VI$. ,

Where, V is the potential difference

P is power dissipated

t is time

Step 2: Using Ohm's law

Now, from ohm's law current can be written as, $I=\frac{V}{R}$.

Step 3: Putting value of $Iintheformulaobtainedinstep1$

$E=VIt=V\times \frac{V}{R}\times t=\frac{V^{2}t}{R}$

Hence, one expression for the electrical energy in terms of its potential difference, resistance, and time =$\frac{V^{2}t}{R}$.