Question
Water can boil in a paper cup. How?

Answer

Water can be boiled in a paper cup the method is as described below:
$i.$ Make a paper cup as shown in the figure.
$ii.$ Pour about 50ml of water in it.
$iii.$ Heat it on a flame as shown in the figure.
$iv.$ After a few minutes of heating you will find that the water in the cup is boiling.
In this process the water is boiled in the paper cup without the cup being burning because when we add water to the cup the ignition temperature of the paper is increased and hence it keeps on transferring the heat that it receives from the candle to the water by the process of conduction and causes the water to boil.

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