Question

Pressure cooker reduces cooking time for food because:

• A. Heat is more evenly distributed in the cooking space
• B. Boiling point of water involved in cooking is increased
• C. The higher pressure inside the cooker crushes the food material
• D. Cooking involves chemical changes helped by a rise in temperature

Answer 1

Correct option: (C)

Boiling point: The boiling point of a substance is the temperature at which the vapour pressure of a liquid is equal to the pressure surrounding the liquid and liquid changes to vapour.

When we normally cook the food, the temperature inside increases until the water starts to boil. And at boiling point, the temperature of the system will not increase, as the heat goes into boiling the water.

But when we cook food inside the pressure cooker, the temperature at which water boils increases because inside the pressure cooker, the pressure increases.

Due to an increase in surrounding pressure, the boiling point temperature also increases. Hence, the heat will increase the temperature of the system instead of boiling the water. Since cooking reactions speed up at higher temperatures, food cooks faster.

Hence, the correct option is (C).