Question

An electric heater draws a current of $11A$, when connected to $220V$ mains supply. Calculate the resistance of the filament of the heater.

Answer 1

Step 1- Given data and formula

1. Potential difference $V=220V$
2. Current $I=11A$

Consider the resistance of the filament of the heater is $R$.

From Ohm's law, the formula for $R$ is

$R=\frac{V}{I}$

Step 2- Finding the resistance of the filament of the heater

Substituting the known values

$$\begin{gathered} R=\frac{V}{I} \\ R=\frac{220V}{11A} \\ R=20\Omega \end{gathered}$$

Hence, the value of the resistance of the filament of the heater is $20\Omega$.