Question

A pressure cooker is based on the principle that the boiling point of water ......... (increases / decreases) with the increase in pressure.

Answer 1

Hint: Pressure cooker is used to cook food by adding water into it. It works by capturing the steam which builds up in the cooker, increasing the pressure in the vessel. Boiling point limits to $100{}^\circ C$ but because of effective cooking temperature, the boiling point increases to $120{}^\circ C$. Therefore cooking time drops substantially.

Complete step by step answer:
We all know that, in our everyday activities, the laws of physics apply. One such example is the working of a pressure cooker, and how it cooks food faster than other cooking utensils.
Internally, a pressure cooker is made up of a lid, a pot, a rubber ring which goes between or fits between the lid and the pot so that no air or pressure will escape and a value on top of the lid to which we also call a whistle. Note that the lid must fit precisely on the pot with a locking system / mechanism.
We used water to cook food in a pressure cooker because it is a better conductor of heat (than air). You can raise the temperature of water to transfer its energy from water to food, basically cooking it. The pressure cooker is based on the principle that a pressure cooker increases the pressure so that the water will come to a boil higher than its regular boiling point which is $100{}^\circ C$. That is its boiling point increases, as pressure increases. Here, pressure is nothing but force applied by the steam. When the amount of temperature increases, production of steam increases likewise pressure due to steam also increases. Therefore, the boiling point decreases.

Note:
Increase in pressure also leads to force the heat into the food. Food inside the cooker does not get smashed because the stem applies uniform pressure to all the surface of the food. Note that steam and pressure is two different things. Steam is the water droplet present inside the cooker having certain energy and energy inside the droplet or steam is not but pressure (Quantity wise).