A heater is connected to a 240 V mains supply and draws a current of 10 A. Calculate the resistance of the heater and the electrical power it consumes.

Step-by-step solution

1. Use Ohm’s law $V=IR$ to find resistance: $R=\frac{V}{I}$.
2. Substitute $V=240\text{V}$ and $I=10\text{A}$, giving $R=\frac{240}{10}=24\Omega$.
3. Now calculate power using $P=VI$.
4. Substitute $V=240\text{V}$ and $I=10\text{A}$, obtaining $P=240\times 10=2400\text{W}$.
5. State both results clearly.

Concept tested: Ohm’s law and electric power

Published 21 August 2026 · How this solution was prepared and checked

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