Question

The temperature of water in the experiment to determine the surface tension of water by capillary rise method remains constant because it affects the
(A) Density
(B) Surface tension
(C) Angle of contact
(D) density and surface tension

Answer 1

Hint We are given a situation where the temperature of water remains constant during a whole experiment which is used to determine the surface tension of water by a capillary rise method and are asked which of the given parameters gets affected by the rise in temperature. Thus, we will discuss the variation of each parameter with the change in temperature.

Complete Step By Step Answer
Firstly,
We are given the option as density.
Now,
A property of density is that it is inversely proportional to the temperature.
That is,
$ \Rightarrow \rho \propto \dfrac{1}{T}$
Where, $\rho $ is the density of the liquid and $T$ is the temperature of the liquid.
Thus,
The change in temperature will affect the density of the water.
Then,
We are given the option as surface tension.
Now,
A property of surface tension is that it is inversely proportional to the temperature.
That is,
$ \Rightarrow S \propto \dfrac{1}{T}$
Where, $S$ is the surface tension of the liquid and $T$ is the temperature of the liquid.
Thus,
The change in temperature will affect the surface tension of the water.
Again,
We are given the option as an angle of contact.
Now,
Clearly,
The angle of contact will not be affected with the change in temperature.
Finally,
Taking into account the discussed parameter, the correct option is $\left( {\text{d}} \right)$ .


Taking into account the discussed parameter, the correct option is (D).

Note We discussed each parameter with respect to the change in temperature assuming that all the other parameters remain constant. Thus, if the case was of discussing the change in the given parameters with respect to change in other parameters of the liquid other than the temperature of the liquid.