Question

$P=\frac{V^2}{R}$ is applied when

• A. Current is constant
• B. Potential difference is constant
• C. Resistance is constant
• D. None

Answer 1

The correct option is B Potential difference is constant

Electric power is given by $P=VI=I^{2}R=\frac{V^2}{R}$

When potential difference applied is constant, we use $P=\frac{V^2}{R}$

When current flowing is constant, we use $P=I^{2}R$