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Poiseuille's Law Formula

Last updated date: 19th May 2024
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Poiseuille's Law Formula is actually one of the most important concepts that the students have to be familiar with. It is not only one that they should learn but also understand thoroughly. This is so they can have a better understanding of their subject, the topic, and its many applications. Students can also have a very good idea about how they can solve various problems related to this topic. This can ultimately help them at the time of their exams when they have to get good marks. 

A topic such as this has to be one that you understand the best. It is because of its importance that you can score well and get good marks in your overall subjects. 

How Vedantu Helps In Practice

With the help of Vedantu, the students can also get the assistance they need in case they have any sort of doubts. There are many teachers who are experts at handling the many queries that the students might have regarding any of the topics in their syllabus.    

Poiseuille’s Law is one that can be understood with the help of the student’s textbooks as well. But when it comes to gaining some much necessary additional insights, the students can get those through the online material. Students can basically learn such things from some of the most trusted sources that there are. They can have their teachers either explain it to them or register on the Vedantu app or the website. With the latter, they can also ask the experts online about their problems along with easily understandable solutions. 

FAQs on Poiseuille's Law Formula

1. What does poiseuille's law explain?

Poiseuille's equation for viscosity used to calculate the viscosity of the liquid through the velocity of the fluid flow through a narrow tube, which varies directly with the pressure and the fourth power of the radius of the tube and is inversely proportional to the length of the tube and coefficient of viscosity. 

Poiseuille's law formula  V = πpr4/8lη

2. What are the Units of Poiseuille's Law?

Derivation of poiseuille's equation can determine the liquid’s viscosity (V) flows through the cylindrical tube. The unit of viscosity is (N/m2)s or Pascal Second (Pa⋅s). The flow of liquid is proportional to the difference between the pressure of two points and inversely proportional to resistance Q=(P2−P1) / R. For the laminar flow of liquid in a tube, Poiseuille’s equation resistance states that R=8ηlπr4.

3. Which factor plays the most important role in Poiseuille's Law Formula?

There is no one, but three most important factors that come into play while using Poiseuille's Law Formula. These are:

  • Vessel Diameter,

  • Vessel Length, and 

  • The viscosity of blood.

If we talk about the most important one out of these three, then it would be the vessel diameter. This is because, when it comes to the vessels, their diameter actually contracts or expands owing to a few factors of its own. It is very common for the vessels to contract or relax in the blood vessel wall. Such a change can also bring about a change in the formula as well. 

4. What is the importance of Poiseuille's Law? 

Poiseuille's Law Formula is used to describe the relationship that is there between the pressure, flow rate, and fluidic resistance. It is also used for the determination of pressure drop pertaining to a constant viscosity fluid. This fluid basically exhibits the laminar flow that goes through a tight pipe. 

One more importance of such a topic is the fact that it is one that comes in the exams for Chemistry. This sets a foundation for the students so they can do better in their higher studies.     

5. How can Vedantu help me to understand Poiseuille’s Law?

There are many ways in which Vedantu can help one with their exams. It becomes the most beneficial at the time when one has to study and have a better understanding of the various topics that are of significance for them in the subject. They can easily get a hold of the numerous topics such as Poisseuille’s Law formula and get some insightful details relating to the topic. They also get a good step-by-step procedure of the derivations as well as the examples and applications. 

6. Write a short note on Poiseuille's?

Poiseuille's Law is an easy way to take out the correct viscosity of the liquid that goes through a narrow tube. The equation uses the velocity of the fluid to calculate. One thing that varies directly during the application of this formula is the pressure with which the liquid flows through the tube. The fourth power of the tube’s radius is also a varying factor. One must keep in mind that there is an inverse proportionality between the velocity of the liquid and the length of the tube. It is also inversely proportional to the coefficient of viscosity. 

Poiseuille's law formula  

V = πpr4/8lη

7. Name the units in which we measure Poiseuille's Law?

The derivation of the Poiseuille's Law Formula is one that can be determined by the liquid’s viscosity (V) that flows via a narrow cylindrical tube. It is the unit of viscosity that can be explained with the help of the following:

  • (N/m2)s, or 

  • Pascal Second (Pa⋅s). 

When it comes to the flow of liquid, it can be stated that there is a direct proportionality between the flow of liquid and the difference present in between the pressure present in two points. There is also an inverse proportionality between the flow of liquid and the presence of resistance Q=(P2−P1) / R.