Properties Of Solids And Liquids Question 337
Question: The surface tension of a liquid is 5 N/m.If a thin film of the area 0.02 m2 is formed on a loop, then its surface energy will be [CPMT 1977; MP PET 1989; BCECE 2005]
Options:
A) $ 5\times 10^{2}J $
B)$ 2.5\times {{10}^{-2}}J $
C) $ 2\times {{10}^{-1}}J $
D)$ 5\times {{10}^{-1}}J $
Show Answer
Answer:
Correct Answer: C
Solution:
$ W=T\times \Delta A=5\times 2\times (0.02) $ (Film has two free surfaces) $ =2\times {{10}^{-1}}J $
