Assertion (A) : In a pressure cooker food is cooked above boiling point. Reason (R) : Boiling point of water increases as the pressure increases.

Assertion (A) is true because a pressure cooker allows food to be cooked at temperatures significantly higher than the standard boiling point of water (100°C). In a sealed pressure cooker, steam is trapped, which increases the internal ambient pressure [t5][t8]. Reason (R) is also true and provides the correct explanation for (A). The boiling point of a liquid is the temperature at which its vapor pressure equals the external pressure [c1][t10]. As the pressure inside the cooker increases, the water molecules require more kinetic energy (higher temperature) to escape into the gaseous state, thus raising the boiling point [c2][t6]. For instance, at 15 psi, the boiling point of water rises to approximately 121°C [t5]. This higher temperature accelerates the chemical reactions involved in cooking, such as breaking down tissues or starches, thereby reducing cooking time [t8][t9].

Sources

1. [1] Science ,Class VIII . NCERT(Revised ed 2025) > Chapter 7: Particulate Nature of Matter > 7.2.2 Liquid state > p. 105
2. [2] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 3: Geological Time Scale The Evolution of The Earths Surface > 3. Geological Time Scale – The Evolution of The Earth's Surface > p. 43