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

• A.
• B. $2.5 \times 10 ^ { - 2 } J$
• C.
• D.

Answer 1

Answer: (C)

Answer 2

$W = T \times \Delta A = 5 \times 2 \times ( 0.02 )$

(Film has two free surfaces)