In a pressure cooker, the temperature at which the food is cooked depends mainly upon which of the following?
- Area of the hole in the lid
- Temperature of the flame
- Weight of the lid
Select the correct answer using the code given below.
1 and 2 only
2 and 3 only
1 and 3 only
1, 2 and 3
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Answer is Wrong!
This question was previously asked in
UPSC IAS – 2021
– The boiling point of water increases with pressure. At standard atmospheric pressure (1 atm), water boils at 100°C (212°F). In a pressure cooker, the pressure can rise to about 2 atm (or more), raising the boiling point to around 120-125°C (248-257°F).
– The maximum pressure inside the cooker is regulated by a pressure release valve, which typically consists of a small hole or vent in the lid covered by a weight or spring mechanism.
– The pressure at which steam is released depends directly on the weight placed on the vent and inversely on the area of the vent hole under the weight. A heavier weight or a smaller hole area will result in higher pressure and thus a higher cooking temperature.
– The temperature of the flame affects the *rate* at which the water heats up and turns into steam, and thus how quickly the desired pressure is reached. However, once the pressure regulator starts venting steam, the temperature inside stabilizes at a level determined by the pressure, not the flame temperature (as long as the heat input is sufficient to maintain that pressure).
– Therefore, the main factors determining the cooking temperature are the weight of the lid (specifically the pressure regulator) and the area of the hole it covers, which together regulate the internal pressure.