Properties Of Solids And Liquids Question 346
Question: What is ratio of surface energy of 1 small drop and 1 large drop, if 1000 small drops combined to form 1 large drop[CPMT 1990]
Options:
A) 100 : 1
B) 1000 : 1
C) 10 : 1
D)1 : 100
Show Answer
Answer:
Correct Answer: D
Solution:
Volume of liquid remain same i.e. volume of 1000 small drops will be equal to volume of one big drop
$ n\frac{4}{3}\pi r^{3}=\frac{4}{3}\pi R^{3} $
$\therefore 1000r^{3}=R^{3} $
$\therefore $ R=10r $
$ \therefore \frac{r}{R}=\frac{1}{10} $
$ \frac{\text{surface energy of one small drop}}{\text{surface energy of one big drop}}=\frac{4\pi r^{2}T}{4\pi R^{2}T}=\frac{1}{100} $
