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प्रश्न
Write scientific reason.
Use a pressure cooker to cook food in cold air.
उत्तर
- Normally, in cold air, more heat energy needs to be supplied to attain high temperatures required for cooking food. It also consumes more time.
- Whereas, pressure cooker operates by giving out the air within the cooker and trapping steam produced from the liquid, (mostly water) boiling inside.
- Due to high internal pressure, boiling point of liquid increases and liquid boils at temperature higher than its boiling point.
- The increased boiling point allows more absorption of heat by liquid and steam formed is superheated causing food to get cooked quickly.
Hence, it is advisable to use a pressure cooker to cook food in cold air.
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