Understanding Capillarity

Capillarity is a simple topic that can be understood easily in terms of Hydrodynamics. Hydrodynamics is that branch of greater physics that deals and copes with the toing and froing of several fluids and the forces which act on solid objects or elements that are immersed in fluids and are in motion. We can easily understand the concept of Capillarity, Capillary actions, and the capillarity of water with the help of this branch of physics. 

To understand Capillarity, we must know its meaning properly. It is an invisible force that works upon the gravitational force. It has the responsibility and capacity to push the liquid up from within a pipe or a tube; the pipe must be narrow for this to happen. This pushing up of the liquid in a tube or piper is the Capillary Action. It is the miraculous ability and capacity of liquids in moving through absorbent materials. This ability is one of the basic physical properties of several liquids. This capacity, indeed, arises due to the attractions. 

In simpler words, Capillarity is the rate through which fluid rises or depresses, when it comes in contact with other solid surfaces. 

Capillary Action

The action or force or ability through which a fluid is pushed up against the force of gravitational attraction in a pipe or a tube is commonly known as the Capillary action. However, this force is not bound to permanence. The fluid falls again after a certain amount of time is passed. This happens because of the Surface Tension and the ratio between the cohesive and adhesive forces. We will discuss the surface tension definition later in this article. 

Some interesting facts about capillary actions are as follows-

• This rise will be according to the shape of the tube or pipe. The narrower the pipe is, the higher the rise-up will be. 

• If the fluid’s density increases, then the rise-up of the fluid will be less. 

• In case anyone of the two phenomena responsible for this rise-up increases, then the fluid rises haphazardly. 

Let us look at an example of Capillary Example, from our daily and common life. Water is a liquid which plays an essential role in our lives. Water moves up against the wave of gravity with the help of a straw or the same water moving through a towel against the actions of gravity. Therefore, this movement is the Capillary Action. It must also be noted that this rise in the division of mercury falls after a certain time. Therefore, both these rises and falls are Capillary Actions. Now, let us look at the meaning of Surface Tension definition, due to which the rise in mercury falls. 

Surface Tension

The meaning of the surface tension definition says that the fluid surfaces equate themselves to the small and minimum surface area given. The tension in the surface of the fluid increases due to the attraction of the particles in the surface’s mass of fluid, which tries and minimizes the area of the surface of the fluid or liquid drop. This phenomenon is widely known as Surface tension. According to the surface tension definition, this phenomenon helps the insects to slide and swim on the wet surface, without them being even partially dipped in the wet area. 

As per the Surface tension definition, let us look at the surface tensions of several liquids-

Therefore, Surface tension is measured as N/m, that is, Newton per metre. Mathematically, it can be done as:

S = f /l

Here, 

• S is the Surface Tension of the fluid

• l is the length, and

• f is the force applied to each unit of the length

Capillarity of water

As we have discussed the meaning of Capillarity and the surface tension definition, let us look at the meaning of Capillarity of water. Let us look at this topic through its application in the physical world.

• The water makes the coffee powder melt easily immediately. This is because the water wets the fine particles of coffee powder due to the capillary action. 

• The shower towel soaks the water and the moisture from our bodies when we use it. This action takes place due to its capillary action. This is also known as capillary water. 

• Another example is the ink rising and the pen, helping in writing on the paper. 

Conclusion

Capillarity is a simple topic that can be understood easily in terms of Hydrodynamics. It is an invisible force that works upon the gravitational force. It has the responsibility and capacity to push the liquid up from within a pipe or a tube; the pipe must be narrow for this to happen. This pushing up of the liquid in a tube or piper is the Capillary Action. The fluid falls again after a certain amount of time is passed. This happens because of the Surface Tension and the ratio between the cohesive and adhesive forces. The meaning of the surface tension definition says that the fluid surfaces equate themselves to the small and minimum surface area given.