In an electric kettle 250 ml water boils in 5 minutes. If the same amount of water needs to be boiled in half of the time by using the same power supply, which of the following conditionswould be applied?
Correct answer: D. Increase the power supply
- A. Increase the impurity in water
- B. Decrease the amount of current
- C. Use the kettle with an open lid
- D. Increase the power supply
Explanation
The correct answer is to increase the power supply. To boil the same amount of water in half the time, the energy input needs to be increased, which can be achieved by increasing the power supply. This allows the kettle to heat the water more quickly, reducing the boiling time. Increasing impurities, using the kettle with an open lid, or decreasing the current would either increase the time needed or make the process less efficient, hence they are not viable solutions.
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