When there is no external force,the shape of a liquid drop is determined by

$A$ metal sheet $4 \ m$ on a side and of negligible thickness is attached to a balance and inserted into a container of fluid. The balance to which the metal sheet is attached reads $0.50 \ N$ and the contact angle is found to be $0^{\circ}$. $A$ small amount of oil is then spread over the metal sheet. The contact angle now becomes $180^{\circ}$ and the balance now reads $0.49 \ N$. The surface tension of the fluid is:

$A$ thin metal wire of density $\rho$ floats on the water surface horizontally. If it is $\text{NOT}$ to sink in water,then the maximum radius of the wire is proportional to $(T = \text{surface tension of water}, g = \text{gravitational acceleration})$.

What causes the free surface of a liquid to have minimum area?

$A$ ring is cut from a platinum tube with an internal diameter of $8.5\, cm$ and an external diameter of $8.7\, cm$. It is supported horizontally from the pan of a balance so that it comes in contact with the water in a glass vessel. If an extra $3.97\, g$ weight is required to pull it away from the water,the surface tension of water is ......... $dyne\, cm^{-1}$.

On what does the value of surface tension depend? Explain.