Question

The beans are cooked earlier in pressure cooker, because

• A. B.P. increase with increasing pressure
• B. B.P. decrease with increasing pressure
• C. extra pressure of pressure cooker, softens the beans
• D. internal energy is not lost while cooking in pressure cooker

Answer 1

The Correct Option is A

The question asks why beans cook faster in a pressure cooker. To answer this, let's first understand the basic principle of how pressure cooking works.

Pressure cookers work by increasing the pressure inside the pot. When the pressure inside the pressure cooker increases, the boiling point of water also increases. Normally, water boils at 100°C (212°F) at standard atmospheric pressure. However, inside a pressure cooker, the pressure is higher than atmospheric pressure, leading to a higher boiling point.

This concept is explained by the physical principle that boiling point (B.P.) increases with increasing pressure. So, when the boiling point of water increases, the water can reach higher temperatures before boiling, thus cooking food faster. In this context, beans cook faster in a pressure cooker because the water temperature reaches higher levels than it would at normal atmospheric pressure, cooking the beans more quickly and thoroughly.

1. Option 1: B.P. increase with increasing pressure: This is the correct explanation of why beans cook faster in a pressure cooker. Higher pressure equals higher boiling point, which cooks food faster.
2. Option 2: B.P. decrease with increasing pressure: This is incorrect. The boiling point increases with increased pressure, not decreases.
3. Option 3: Extra pressure of pressure cooker, softens the beans: While the pressure assists in increased boiling temperature, the key reason is the rise in the boiling point and not directly the softening due to pressure itself.
4. Option 4: Internal energy is not lost while cooking in pressure cooker: This statement is somewhat misleading. While energy retention is a benefit, the primary reason for quicker cooking time is the elevation of boiling point and temperature.

Therefore, the correct answer is that the boiling point increases with increasing pressure, making the cooking process faster in a pressure cooker.