A) \[2\pi ({{D}^{2}}-{{d}^{2}})S\]
B) \[\pi ({{D}^{2}}-{{d}^{2}})S\]
C) \[4\pi ({{D}^{2}}-{{d}^{2}})S\]
D) \[8\pi ({{D}^{2}}-{{d}^{2}})S\]
Correct Answer: A
Solution :
Change in surface area \[=2\times 4\pi \left[ {{\left( \frac{D}{2} \right)}^{2}}-{{\left( \frac{d}{2} \right)}^{2}} \right]=2\pi ({{D}^{2}}-{{d}^{2}})\] \[\therefore \] Work done = surface tension \[\times \] change in area \[=2\pi S({{D}^{2}}-{{d}^{2}})\]
You need to login to perform this action.
You will be redirected in
3 sec
