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An external pressure P is applied on a cube at 0° 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

Answer:

Explanation:

$K = \frac{P}{(-\triangle V/V)}$

  $\Rightarrow   -\frac{\triangle V}{V}=\frac{P}{K}$

$\Rightarrow   -\triangle V=\frac{PV}{K}$

change in volume $\triangle V= \gamma V \triangle T$ 

  where $\gamma$ = coefficient of volume expansion

  Again , $\gamma = 3\alpha$

  $\alpha$ is coefficient of linear expansion

$\therefore$       Δ V =V (3 $\alpha$)ΔT

$\therefore    \frac{PV}{K}=V (3\alpha)\triangle T$

$\therefore    \triangle T= \frac{P}{3\alpha K}$