Which of the following gas laws is applied in a pressure cooker?

The gas law applied in a pressure cooker is the Gay-Lussac's Law. Here's a step-by-step explanation:

1. Gay-Lussac's Law states that the pressure of a gas is directly proportional to its absolute temperature, provided its volume is kept constant.

2. In a pressure cooker, the volume is kept constant because the cooker is sealed.

3. As the temperature inside the cooker increases, the pressure also increases. This is because the heat causes the gas particles to move faster and collide more frequently with the walls of the cooker, thereby increasing the pressure.

4. The increased pressure allows the temperature to rise above the normal boiling point of water, which speeds up the cooking process.

5. When the pressure reaches a certain point, the pressure valve releases some of the gas to prevent the pressure from becoming too high.

So, the operation of a pressure cooker is a practical application of Gay-Lussac's Law.