Question

A drop of liquid of density `rho` is floating half-immersed in a liquid of density `d`. If `rho` is the surface tension the diameter of the drop of the liquid is
A. `sqrt((sigma)/(g(2rho-d)))`
B. `sqrt((2sigma)/(g(2rho-d)))`
C. `sqrt((6sigma)/(g(2rho-d)))`
D. `sqrt((12sigma)/(g(2rho-d)))`

Answer 1

Correct Answer - D
`2pirsigma+1/2xx4/3pir^(3)dg=4/3rhog`
or `2pirsigma=(pir^(3)g)/3[4rho-2d]` or `r^(2)=(3xx2pisigma)/(pig(2rho-2d)`
or `r^(2)=(3sigma)/(g(2rho-d)` or `r=sqrt((3sigma)/(g(2rho-d)))`
Diameter `=2r=sqrt((12sigma)/(g(2rho-d))`