Question

A weight thermometer contains 52 gms of a liquid at 10${}^0$C. When it is heated to 110${}^0$C, 2 gm of the liquid is expelled. The coefficient of real expansion of the liquid is [$\alpha$ of glass is $9\times {10}^{-6/0}C$]

• A. $27\times {10}^{-6/0}C$
• B. $412\times {10}^{-6/0}C$
• C. $373\times {10}^{-6/0}C$
• D. 0

Answer 1

Answer: (B)

$412\times {10}^{-6/0}C$

$V_{expelled}=V_0({\gamma }_l-{\gamma }_g)\Delta T$
$\Rightarrow 2=52\times ({\gamma }_l-3\times {\alpha }_g)\times (110-10)$
$\Rightarrow 2=52\times ({\gamma }_l-3\times 9\times {10}^{-6})\times 100$
$\Rightarrow {\gamma }_l=\frac{2}{52}\times {10}^{-2}+27\times {10}^{-6}=385\times {10}^{-6}+27\times {10}^{-6}=412\times {10}^{-6}$