question_answer

An external pressure P is applied on a cube at \[0{{\,}^{o}}C\]so that it is equally compressed from all sides. K is the bulk modulus of the material of the cube and\[\alpha \]is its coefficient of linear expansion. Suppose we want to bring the cube to its original size by heating. The temperature should be raised by:                                      [JEE Main 2017]

A)  \[\frac{3\alpha }{PK}\] 

B)       \[3PK\alpha \]

C)  \[\frac{P}{3\alpha K}\] 

D)      \[\frac{P}{\alpha K}\] Correct Answer: C Solution : [c] Due to thermal expansion

Due to External pressure

Equating both get