In a resistive circuit, the power dissipated by a resistor \( R \) when a current \( I \) flows through it is given by \( P = I^2 R \). What happens to the power when the current is doubled?
Show Hint
- It quadruples
- It doubles
- It remains the same
- It is halved
The Correct Option is A
Solution and Explanation
The power dissipated in a resistor is given by \( P = I^2 R \). If the current is doubled, i.e., \( I \rightarrow 2I \), the power becomes: \[ P' = (2I)^2 R = 4I^2 R. \]
Thus, the power quadruples when the current is doubled.
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