JEE Main Solved Paper 2017 Question 25
Question: 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 Solved Paper-2017]
Options:
A) $ \frac{3\alpha }{PK} $
B) $ 3PK\alpha $
C) $ \frac{P}{3\alpha K} $
D) $ \frac{P}{\alpha K} $
Show Answer
Answer:
Correct Answer: C
Solution:
- Due to thermal expansion $ \frac{\Delta v}{v}=3\alpha \Delta T $ Due to External pressure $ \frac{\Delta v}{v}=\frac{P}{K} $ Equating both $ w _1 $ get $ 3\alpha \Delta T=\frac{P}{K} $ $ \Delta T=\frac{P}{3\alpha K} $
