Q. In a pressure cooker, the temperature at which the food is cooked depends mainly upon which of the following?
1.Area of the hole in the lid
2.Temperature of the flame
3.Weight of the lid
Select the correct answer using the code given below.
a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2 and 3
Correct Answer: c) 1 and 3 only
Question from UPSC Prelims 2021 GS Paper
Explanation :
Pressure Cooker Cooking Temperatures
The correct answer is “1 and 3 only,” which means that the temperature at which the food is cooked in a pressure cooker depends mainly upon the area of the hole in the lid and the weight of the lid.
Area of the Hole in the Lid
The area of the hole, or vent, in the lid of a pressure cooker is critical because it determines the pressure that can be maintained inside the cooker. A pressure cooker works by trapping steam inside, which increases the pressure and consequently raises the boiling point of water. The size of the hole is usually designed to allow just enough steam to escape to maintain a specific pressure, which correlates with a specific temperature. If the hole were larger, the pressure would be lower, and the temperature would be reduced.
Temperature of the Flame
While the temperature of the flame does affect how quickly the pressure cooker reaches the desired pressure, it does not directly determine the cooking temperature once the cooker has reached pressure. The cooking temperature is primarily set by the pressure inside the cooker, which is controlled by the design of the pressure valve (related to the area of the hole) and the weight on the lid.
Weight of the Lid
The weight of the lid, or more specifically, the weight of the pressure regulator that sits on the vent pipe, plays a direct role in controlling the pressure inside the cooker. The heavier the weight, the higher the pressure that can be maintained before steam is allowed to escape. This higher pressure results in a higher cooking temperature. In many pressure cookers, different weights can be used to achieve different pressures, which correspond to different cooking temperatures.
Official Answer by UPSC is c
