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Water boils in an electric kettle in $20$ minutes after being switched on. Using the same main supply, the length of the heating element should be. . . . . . .to . . . . . .. times of its initial length if the water is to be boiled in $15$ minutes.
  • Aincreased, $\frac{3}{4}$
  • Bincreased, $\frac{4}{3}$
  • Cdecreased, $\frac{3}{4}$
  • Ddecreased, $\frac{4}{3}$
JEE MAIN 2024, Diffcult
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