Detailed Explanation:

Answer: Option 3 — 1 and 3 Only

In a pressure cooker, the cooking temperature depends on the internal pressure, which determines the boiling point of water. The area of the hole in the lid and the weight of the lid regulate how much pressure builds up inside the cooker, thereby controlling the cooking temperature. The flame temperature only affects the rate of heating, not the maximum temperature achieved.

✅ Statement 1 – Correct: The size of the hole in the lid regulates steam release; a larger hole allows more steam to escape, reducing internal pressure and thus lowering the cooking temperature.

❌ Statement 2 – Incorrect: The temperature of the flame affects only the rate of heating, not the final cooking temperature, which is determined by the internal pressure of the cooker.

✅ Statement 3 – Correct: A heavier weight on the lid requires higher internal pressure to lift it, allowing steam to escape only when higher pressure is reached, which increases the boiling point and thus the cooking temperature.

📝 Short Notes: Pressure Cooker Mechanism

• Principle: Pressure cookers work on the principle that increasing pressure raises the boiling point of water above 100°C.
• Normal Boiling Point: At atmospheric pressure (1 atm), water boils at 100°C.
• In Pressure Cooker: Pressure can reach 15 psi (about 2 atm), raising the boiling point to approximately 121°C.
• Pressure Regulation: The weight (regulator) on the vent controls the maximum pressure by allowing steam to escape when pressure exceeds a threshold.
• Vent Hole Size: The area of the vent hole determines how easily steam can escape, affecting pressure buildup.
• Cooking Time: Higher temperature due to increased pressure reduces cooking time significantly.
• Flame Role: The flame intensity affects how quickly the cooker reaches operating pressure, not the final cooking temperature.