Question

What is the ratio of surface energy of $1$ small drop and $1$ large drop if $1000$ drops combined to form $1$ large drop?

• A. 100 : 1
• B. 1000 : 1
• C. 10 : 1
• D. 1 : 100

Answer 1

Answer: (D)

As, $\frac{4}{3}\pi R^3=1000\times \frac{4}{3}\pi r^3$
$\Rightarrow R=10r$
Surface energy of small drop $E_1=S\times 4\pi r^2$
Surface energy of large drop $E_2=S\times 4\pi (10r{)}^2$
$\therefore E_1/E_2=1/100$