Access free live classes and tests on the app
Download
+
Unacademy
  • Goals
    • AFCAT
    • AP EAMCET
    • Bank Exam
    • BPSC
    • CA Foundation
    • CAPF
    • CAT
    • CBSE Class 11
    • CBSE Class 12
    • CDS
    • CLAT
    • CSIR UGC
    • GATE
    • IIT JAM
    • JEE
    • Karnataka CET
    • Karnataka PSC
    • Kerala PSC
    • MHT CET
    • MPPSC
    • NDA
    • NEET PG
    • NEET UG
    • NTA UGC
    • Railway Exam
    • SSC
    • TS EAMCET
    • UPSC
    • WBPSC
    • CFA
Login Join for Free
avtar
  • ProfileProfile
  • Settings Settings
  • Refer your friendsRefer your friends
  • Sign outSign out
  • Terms & conditions
  • •
  • Privacy policy
  • About
  • •
  • Careers
  • •
  • Blog

© 2023 Sorting Hat Technologies Pvt Ltd

Watch Free Classes
    • Free courses
    • JEE Main 2024
    • JEE Main 2024 Live Paper Discussion
    • JEE Main Rank Predictor 2024
    • JEE Main College Predictor 2024
    • Stream Predictor
    • JEE Main 2024 Free Mock Test
    • Study Materials
    • Notifications
    • JEE Advanced Syllabus
    • JEE Books
    • JEE Main Question Paper
    • JEE Coaching
    • Downloads
    • JEE Notes & Lectures
    • JEE Daily Videos
    • Difference Between
    • Full Forms
    • Important Formulas
    • Exam Tips
JEE Main 2026 Preparation: Question Papers, Solutions, Mock Tests & Strategy Unacademy » JEE Study Material » Physics » Torricelli’s Law

Torricelli’s Law

In this article, study about Torricelli’s law, use of Torricelli’s law and Its application.

Table of Content
  •  

Torricelli’s theorem, also known as Torricelli’s law, Torricelli’s principle, or Torricelli’s equation, states that the speed, v, of a liquid flowing under gravity out of an opening in a tank is proportional to the square root of the vertical distance, h, between the liquid surface and the centre of the opening and the square root of twice the acceleration caused by gravity,  simply v=(2gh)1/2. (At the Earth’s surface, gravity causes an acceleration of around 32.2 feet per second per second, or 9.8 metre per second per second.) Evangelista Torricelli, who discovered the theorem in 1643, is named for him.

Torricelli’s Law

Torricelli’s law, also called Torricelli’s principle or Torricelli’s theorem, is a fluid dynamics statement that specifies the efflux velocity from orifice.

According to Torricelli’s law, the speed at which fluid flows from an orifice is equal to the speed It would descend freely for a distance equal to the free surface height of the liquid above the aperture.

Consider any vessel having a slit (orifice) filled with liquid.

The fluid will begin to flow through the slit, and according to Torricelli’s law, the speed with which the fluid will flow is equal to the speed with which a freely falling body reaches a height equal to the height of the slit from the fluid’s free surface.

The distance between the free surface and the slit should be equal to h.

The velocity with which the fluid flows is identical to the velocity attained by a freely falling body falling from a height of h.

Torricelli’s law, also known as Torricelli’s principle or Torricelli’s theorem, is a statement in fluid dynamics that the speed, v, of fluid flowing out of an orifice in a tank under gravity is proportional to the square root of the vertical distance, h, between the liquid surface and the centre of the orifice, and to the square root of twice the acceleration caused by gravity.

In other words, the fluid’s efflux velocity from the orifice is the same as it would have been if it had fallen h feet under gravity. Evangelista Torricelli, an Italian scientist, discovered the law in 1643 and named it after him. Later, it was discovered to be a special case of Bernoulli’s principle.

                                        p1+1 / 2pv1²+pgh1=p2+1 / 2pv2²+pgh2 

For a certain circumstance, Torricelli’s equation is derived. Viscosity and other losses must be ignored, and the orifice must be tiny. In Bernoulli’s Equation, if a fluid is flowing through a very small orifice (for example, at the bottom of a big tank), the velocity of the fluid at the large end can be ignored. Furthermore, efflux velocity is unaffected by flow direction. The efflux speed of fluid passing through the opening is thus given by the formula:

                                                      v= √2gh

Use of Torricelli’s law

Torricelli’s law is useful in everyday situations. The physical law describes a significant link between liquid exit velocity and container height. This post will teach you about this relationship and how to use Torricelli’s theorem to calculate exit velocity.

Applications

Horizontal distance covered by the jet of liquid

The horizontal distance traversed by the jet of liquid to reach the same level as the base of the liquid column can be simply calculated if display style HH is the height of the orifice above the ground and display style HH is the height of the liquid column from the ground (height of liquid’s surface). We have from the rules of falling bodies that display style HH is the vertical height travelled by a particle of jet stream.

h=1 / 2gt²=>t= √2h / g ,

Clepsydra problem

A clepsydra is a clock that uses the movement of water to measure time. It is made up of a pot with a little hole at the bottom that allows the water to escape. The amount of water that escapes determines the length of time. According to Torricelli’s law, the rate of efflux via the hole is proportional to the water level, and the discharge is not uniform as the water level drops. Keeping the water level steady is a simple method. This can be accomplished by allowing a continual stream of water to flow into the vessel, with the overflow being permitted to exit via another hole at the top.

     An inflow clepsydra

As a result of the consistent height, the discharging water from the bottom can be collected in a second cylindrical vessel with a uniform graduation for time measurement. This is a clepsydra with inflow.

Alternatively, the water level in the vessel can be controlled to decline at a moderate pace by carefully selecting the vessel’s design. The time can be measured with uniform graduation by monitoring the level of water remaining in the vessel.

Conclusion

Torricelli’s theorem, also known as Torricelli’s law, Torricelli’s principle, or Torricelli’s equation, states that the speed, v, of a liquid flowing under gravity out of a tank opening is proportionate to the square root of the vertical distance, h, between the liquid surface and the centre…

faq

Frequently Asked Questions

Get answers to the most common queries related to the JEE Examination Preparation.

write a short note on Torricelli’s law?

Ans. What happens when a liquid container bursts open? Depending on several conditions, such as the viscosity of the...Read full

Torricelli's Law of Efflux should be explained.

Ans. The speed of efflux of a fluid represented by ‘v’ through a sharp-edged hole at the bottom of a tan...Read full

Describe what Torricelli's Law refers to.

Ans. Torricelli’s theorem, also known as Torricelli’s law, Torricelli’s principle, or Torricelli&#...Read full

Ans. What happens when a liquid container bursts open? Depending on several conditions, such as the viscosity of the liquid and the size of the hole, the liquid may emerge as a forceful spurt or a simple trickle. The depth of the leak within the container is another crucial determining factor. Liquid at a greater depth in the container is really under pressure, which causes the liquid to flow faster through a hole in the container.

Ans. The speed of efflux of a fluid represented by ‘v’ through a sharp-edged hole at the bottom of a tank filled to a depth denoted by the letter ‘h’ is equal to the speed of a body, according to the law. This is the average speed at which a drop of water would fall freely from a height of h.

Ans. Torricelli’s theorem, also known as Torricelli’s law, Torricelli’s principle, or Torricelli’s equation, holds that the speed of a liquid flowing under gravity’s force out of an opening in a tank is proportional to the square root of the vertical distance h between the liquid surface and the centre.

Crack IIT JEE with Unacademy

Get subscription and access unlimited live and recorded courses from India’s best educators

  • Structured syllabus
  • Daily live classes
  • Ask doubts
  • Tests & practice
Learn more

Notifications

Get all the important information related to the JEE Exam including the process of application, important calendar dates, eligibility criteria, exam centers etc.

Allotment of Examination Centre
JEE Advanced Eligibility Criteria
JEE Advanced Exam Dates
JEE Advanced Exam Pattern 2023
JEE Advanced Syllabus
JEE Application Fee
JEE Application Process
JEE Eligibility Criteria 2023
JEE Exam Language and Centres
JEE Exam Pattern – Check JEE Paper Pattern 2024
JEE Examination Scheme
JEE Main 2024 Admit Card (OUT) – Steps to Download Session 1 Hall Ticket
JEE Main Application Form
JEE Main Eligibility Criteria 2024
JEE Main Exam Dates
JEE Main Exam Pattern
JEE Main Highlights
JEE Main Paper Analysis
JEE Main Question Paper with Solutions and Answer Keys
JEE Main Result 2022 (Out)
JEE Main Revised Dates
JEE Marking Scheme
JEE Preparation Books 2024 – JEE Best Books (Mains and Advanced)
Online Applications for JEE (Main)-2022 Session 2
Reserved Seats
See all

Related articles

Learn more topics related to Physics
Zinc-Carbon Cell

The battery you use every day in your TV remote or torch is made up of cells and is also known as a zinc-carbon cell. Read on to know more.

ZEROTH LAW OF THERMODYNAMICS

Read about the Zeroth law of thermodynamics. Learn about the zeroth law definitions and their examples.

Zener Diode As A Voltage Regulator

Understand the concepts of Zener diodes. Also, learn about the efficiency and limitations of Zener Diode as a Voltage Regulator.

Zener diode as a voltage regulator

zener diode is a very versatile semiconductor that is used for a variety of industrial processes and allows the flow of current in both directions.It can be used as a voltage regulator.

See all
Access more than

10,505+ courses for IIT JEE

Get subscription

Trending Topics

  • JEE Main 2024
  • JEE Main Rank Predictor 2024
  • JEE Main Mock Test 2024
  • JEE Main 2024 Admit Card
  • JEE Advanced Syllabus
  • JEE Preparation Books
  • JEE Notes
  • JEE Advanced Toppers
  • JEE Advanced 2022 Question Paper
  • JEE Advanced 2022 Answer Key
  • JEE Main Question Paper
  • JEE Main Answer key 2022
  • JEE Main Paper Analysis 2022
  • JEE Main Result
  • JEE Exam Pattern
  • JEE Main Eligibility
  • JEE College predictor
combat_iitjee

Related links

  • JEE Study Materials
  • CNG Full Form
  • Dimensional Formula of Pressure
  • Reimer Tiemann Reaction
  • Vector Triple Product
  • Swarts Reaction
  • Focal length of Convex Lens
  • Root mean square velocities
  • Fehling’s solution
testseries_iitjee
Subscribe Now
. document.querySelector('.targetTopBtn').onClick = topFunction; function topFunction() { window.scrollTo({ top: 0, behavior: 'smooth' }) }
Company Logo

Unacademy is India’s largest online learning platform. Download our apps to start learning


Starting your preparation?

Call us and we will answer all your questions about learning on Unacademy

Call +91 8585858585

Company
About usShikshodayaCareers
we're hiring
BlogsPrivacy PolicyTerms and Conditions
Help & support
User GuidelinesSite MapRefund PolicyTakedown PolicyGrievance Redressal
Products
Learner appLearner appEducator appEducator appParent appParent app
Popular goals
IIT JEEUPSCSSCCSIR UGC NETNEET UG
Trending exams
GATECATCANTA UGC NETBank Exams
Study material
UPSC Study MaterialNEET UG Study MaterialCA Foundation Study MaterialJEE Study MaterialSSC Study Material

© 2026 Sorting Hat Technologies Pvt Ltd

Unacademy
  • Goals
    • AFCAT
    • AP EAMCET
    • Bank Exam
    • BPSC
    • CA Foundation
    • CAPF
    • CAT
    • CBSE Class 11
    • CBSE Class 12
    • CDS
    • CLAT
    • CSIR UGC
    • GATE
    • IIT JAM
    • JEE
    • Karnataka CET
    • Karnataka PSC
    • Kerala PSC
    • MHT CET
    • MPPSC
    • NDA
    • NEET PG
    • NEET UG
    • NTA UGC
    • Railway Exam
    • SSC
    • TS EAMCET
    • UPSC
    • WBPSC
    • CFA

Share via

COPY