Question

Energy needed in breaking a drop of radius R into n drops of radii r is given by

• A. $4 \pi T \left( n r ^ { 2 } - R ^ { 2 } \right)$
• B. $\frac { 4 } { 3 } \pi \left( r ^ { 3 } n - R ^ { 2 } \right)$
• C. $4 \pi T \left( R ^ { 2 } - n r ^ { 2 } \right)$
• D. $4 \pi T \left( n r ^ { 2 } + R ^ { 2 } \right)$

Answer 1

Answer: (A)

$4 \pi T \left( n r ^ { 2 } - R ^ { 2 } \right)$

Answer 2

Energy needed = Increment in surface energy

= (surface energy of n small drops) –

(surface energy of one big drop)