Water boils in an electric kettle in `15 min` after being switched on . Using the same main supply , should the length of the heating element be increased or decreased if the water is to be boiled in `10 min`? Why ?

Explanation

To determine whether the length of the heating element in an electric kettle should be increased or decreased to boil water in 10 minutes instead of 15 minutes, we can follow these steps:

### Step 1: Understand the relationship between power, resistance, and time
The power \( P \) consumed by the heating element can be expressed using the formula:
\[ P = \frac{V^2}{R} \]
where \( V \) is the voltage and \( R \) is the resistance of the heating element.
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