A bakelite beaker has volume capacity of 500 cc at 30oC. When it is partially filled with Vm volume (at 30oC) of mercury, it is found that the unfilled volume of the beaker remains constant as temperature is varied. If $\gamma$(beaker) = 6 × 10–6 oC–1 and $\gamma$(mercury) = 1.5 × 10–4 oC–1, where $\gamma$ is the coefficient of volume expansion, then Vm (in cc) is close to ____.
Answer (integer)
20
Solution
$\Delta$V = V$\gamma$$\Delta$T
<br><br>$\therefore$ V<sub>1</sub>$\gamma$<sub>1</sub> = V<sub>2</sub>$\gamma$<sub>2</sub>
<br><br>$\Rightarrow$ 500 $\times$ 6 $\times$ 10<sup>-6</sup> = V<sub>m</sub>
$\times$ 1.5 $\times$ 10<sup>-4</sup>
<br><br>$\Rightarrow$ V<sub>m</sub> = ${{500 \times 6 \times {{10}^{ - 6}}} \over {1.5 \times {{10}^{ - 4}}}}$
<br><br>$\Rightarrow$ V<sub>m</sub> = 20 cc
About this question
Subject: Physics · Chapter: Thermodynamics · Topic: Zeroth and First Law
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