Question

If current flowing in an electric kettle is tripled, heat produced in the kettle will become:

• A. four times
• B. three times
• C. nine times
• D. twelve times

Hint:

The heat produced in a resistive element is proportional to the square of the current, as per the formula \( H = I^2 R t \).

Answer 1

The Correct Option is C

The heat produced in an electric kettle (or any electrical heating device) is given by the formula: \[ H = I^2 R t \]
where:
- \( H \) is the heat produced, - \( I \) is the current, - \( R \) is the resistance of the kettle, and - \( t \) is the time for which the current flows.
Step 1: Analyze the effect of tripling the current.
From the formula, we can see that the heat produced is directly proportional to the square of the current \( I^2 \). This means that if the current is tripled, the heat produced will increase by a factor of: \[ \left(\frac{I_{\text{new}}}{I_{\text{old}}}\right)^2 = 3^2 = 9 \]
Step 2: Conclusion.
Thus, if the current flowing in the electric kettle is tripled, the heat produced will become nine times. The correct answer is (C).