When liquid medicine of density `rho` is to be put in the eye, it is done with the help of a dropper. As the bulb on the top of the dropper is pressed, a drop forms at the opening. We first assume that the drop formed at the opening is spherical because that requires in its surface energy . To determine the size, we calculate the net verticle force due to the surface tension T when the radius of the drop is R. when the force becomes smaller than weight of the drop, the drop gets detached from the dropper.
ii. If `r=5xx10^-4m, rho=10^3 kg. m^-3, g=10m.s^-2, T = 0.11 N. m^-1` the radius of the drop when it detaches from the dropper is approximately

Options

A. `.14xx10^-3` m
B. `3.3xx10^-3 ` m
C. `2.0xx10^-3 m`
D. `4.1 xx10^-3 ` m

Answer

A