Properties Of Solids And Liquids Question 103
Question: The coefficient of volumetric expansion of mercury is 18 × 10?5/ºC. A thermometer bulb has a volume 10?6 m3 and cross section of stem is 0.004 cm2. Assuming that bulb is filled with mercury at 0ºC then the length of the mercury column at 100ºC is [Pb. PMT 1998, DPMT 1997, 2001]
Options:
A) 18.8 mm
B) 9.2 mm
C) 7.4 cm
D) 4.5 cm
Show Answer
Answer:
Correct Answer: D
Solution:
V = V0(1 + g Dq)
therefore Change in volume $ V-V _{0}=\Delta V=A.\Delta l=V _{0}\gamma \Delta \theta $
therefore Dl = $ \frac{V _{0}.\Delta \theta }{A} $ = $ \frac{{{10}^{-6}}\times 18\times {{10}^{-5}}\times (100-0)}{0.004\times {{10}^{-4}}} $ = 45 × 10?3 m = 4.5 cm
