Question

The number of drops of water, counted in the falling-drop method using a stalagmometer is $100$ , whereas the number of drops of an organic liquid is $280$ . Calculate the surface tension of the organic liquid if the surface tension of water is $0.07275N{m^{ - 1}}$ and the densities of water and the organic liquid are $0.998 \times {10^3}kg{m^{ - 3}}$ and $0.755 \times {10^3}kg{m^{ - 3}}$ respectively.

Answer 1

We know that the stalagmometric technique is perhaps the most well-known strategy for estimating surface pressure. The standard is to quantify the heaviness of drops of a liquid of interest tumbling from a hair like glass tube, and subsequently ascertain the surface pressure of the liquid. We can decide the heaviness of the falling drops by checking them. From it we can decide the surface strain.

Complete answer:
The number of water drops is $100$.
The number of oil drops is $280$.
It is given that the surface tension of the organic liquid if the surface tension of water is $0.07275N{m^{ - 1}}\;$.
The density of water is $0.998 \times {10^3}kg{m^{ - 3}}$.
The density of organic liquid is $0.755 \times {10^3}kg{m^{ - 3}}$.
Formula used to solve the given problem is,
$\dfrac{{{\gamma _0}}}{{{\gamma _w}}} = \dfrac{{{d_0}}}{{{d_w}}}.\dfrac{{{n_w}}}{{{n_0}}}$
Calculation:
$\dfrac{{{\gamma _0}}}{{0.07275}} = \dfrac{{0.755 \times {{10}^3}}}{{0.998 \times {{10}^3}}}.\dfrac{{100}}{{280}}$
${\gamma _0} = 0.019656N/m$

Note:
We have to know that a stalagmometer is a gadget for exploring surface strain utilizing the stalagmometric technique. It is additionally called a stactometer or stalagmometer. The gadget is a hair-like glass tube whose center segment is extended. The volume of a drop can be foreordained by the plan of the stalagmometer. The lower end of the cylinder is limited to constrain the liquid to drop out of the cylinder as a drop. In an investigation, the drops of liquid stream gradually from the cylinder an upward way. The drops holding tight the lower part of the cylinder begin to fall when the volume of the drop arrives at a most extreme worth that is reliant upon the attributes of the arrangement. As of now, the heaviness of the drops is in harmony with the surface pressure.