Jove
Visualize
Contact Us

Related Concept Videos

Surface Tension, Capillary Action, and Viscosity02:57

Surface Tension, Capillary Action, and Viscosity

Surface Tension
The various IMFs between identical molecules of a substance are examples of cohesive forces. The molecules within a liquid are surrounded by other molecules and are attracted equally in all directions by the cohesive forces within the liquid. However, the molecules on the surface of a liquid are attracted only by about one-half as many molecules. Because of the unbalanced molecular attractions on the surface molecules, liquids contract to form a shape that minimizes the number...
Viscosity01:27

Viscosity

Viscosity is a property of fluids that measures their resistance to flow. It is influenced by factors such as the surface area of contact, the gradient of flow speed, and the fluid's viscosity constant, called the coefficient of viscosity. The coefficient of viscosity, also known as dynamic viscosity, is denoted by the symbol η. It determines the proportionality between the viscous force and the gradient of flow speed.Newton's law of viscosity states that the viscous force on a faster-moving...
Viscosity01:17

Viscosity

When water is poured into a glass, it falls freely and quickly, whereas if honey or maple syrup is poured over a pancake, it flows slowly and sticks to the surface of the container. This difference in the flow of different kinds of liquids arises due to the fluid friction between the liquid layers and the liquid and the surrounding material. This property of fluids is called fluid viscosity. In this example, water has a lower viscosity than honey and maple syrup.
The SI unit of viscosity is...
Viscosity of Fluid01:19

Viscosity of Fluid

Viscosity measures the resistance a fluid offers to flow and deformation. It results from internal friction between layers of fluid moving relative to one another. Dynamic viscosity, denoted by the Greek letter mu (μ), quantifies the force needed to move one fluid layer over another. For Newtonian fluids like water and air, the relationship between the shearing stress and the rate of shearing strain is linear, meaning their viscosity remains constant regardless of the applied stress.
Newtonian Fluid: Problem Solving01:18

Newtonian Fluid: Problem Solving

Newtonian fluids exhibit a constant viscosity, meaning their shear stress and shear strain rate are directly proportional. This property ensures a predictable and stable response to applied forces, maintaining a linear relationship between force and flow. Examples include water, air, and light oils, consistently demonstrating this proportional behavior regardless of external conditions.
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
Stokes' Law01:20

Stokes' Law

Viscous forces, like friction, are intermolecular forces that resist the relative motion of molecules over each other. When a solid body moves through a liquid, viscous forces drag it in the opposite direction. The force's magnitude depends on the solid's shape and size, as well as its speed and the liquid's coefficient of viscosity, density and temperature.
The expression for the force on a solid spherical object in a fluid is called Stokes' law. Stokes' law is valid only for low Reynolds...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

A splay-twist phase stabilized by the interaction between the nematic and torsional fields in nematics.

Soft matter·2025
Same author

Effective optimization of irrigation networks with pressure-driven outflows at randomly selected installation nodes.

Scientific reports·2023
Same author

Nonlinear behavior of the impedance spectrum of a kerosene based ferrofluid.

Physical chemistry chemical physics : PCCP·2022
Same author

Does conjugation strategy matter? Cetuximab-conjugated gold nanocages for targeting triple-negative breast cancer cells.

Nanoscale advances·2022
Same author

Ions, adsorption and electric response of a ferrofluid cell.

Physical chemistry chemical physics : PCCP·2022
Same author

Free ions in kerosene-based ferrofluid detected by impedance spectroscopy.

Physical chemistry chemical physics : PCCP·2021
Same journal

Tension on dsDNA bound to ssDNA-RecA filaments may play an important role in driving efficient and accurate homology recognition and strand exchange.

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Publisher's Note: Amplitude-phase coupling drives chimera states in globally coupled laser networks [Phys. Rev. E 91, 040901(R) (2015)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Erratum: Shapes of sedimenting soft elastic capsules in a viscous fluid [Phys. Rev. E 92, 033003 (2015)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Erratum: Attenuation of excitation decay rate due to collective effect [Phys. Rev. E 90, 022142 (2014)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Publisher's Note: Role of connectivity and fluctuations in the nucleation of calcium waves in cardiac cells [Phys. Rev. E 92, 052715 (2015)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
Same journal

Publisher's Note: Lattice Boltzmann approach for complex nonequilibrium flows [Phys. Rev. E 92, 043308 (2015)].

Physical review. E, Statistical, nonlinear, and soft matter physics·2016
See all related articles
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Video

Updated: Jun 22, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
06:24

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal

Published on: October 31, 2019

Surface viscosity in nematic liquid crystals.

G Barbero1, L Pandolfi

  • 1Dipartimento di Fisica and CNISM, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy.

Physical Review. E, Statistical, Nonlinear, and Soft Matter Physics
|June 13, 2009
PubMed
Summary
This summary is machine-generated.

Localized surface viscosity influences nematic liquid crystal relaxation dynamics. This effect is significant for slow dynamics, validating its use in describing these phenomena.

More Related Videos

Forming, Confining, and Observing Microtubule-Based Active Nematics
08:37

Forming, Confining, and Observing Microtubule-Based Active Nematics

Published on: January 13, 2023

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids
10:28

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids

Published on: January 3, 2014

Related Experiment Videos

Last Updated: Jun 22, 2026

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal
06:24

High-Contrast and Fast Photorheological Switching of a Twist-Bend Nematic Liquid Crystal

Published on: October 31, 2019

Forming, Confining, and Observing Microtubule-Based Active Nematics
08:37

Forming, Confining, and Observing Microtubule-Based Active Nematics

Published on: January 13, 2023

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids
10:28

Experimental Measurement of Settling Velocity of Spherical Particles in Unconfined and Confined Surfactant-based Shear Thinning Viscoelastic Fluids

Published on: January 3, 2014

Area of Science:

  • Materials Science
  • Physics
  • Physical Chemistry

Background:

  • Nematic liquid crystals exhibit complex relaxation dynamics.
  • Surface properties significantly influence bulk material behavior.
  • Understanding surface viscosity is crucial for predicting material response.

Purpose of the Study:

  • To investigate the impact of localized surface viscosity on deformation relaxation in nematic liquid crystals.
  • To analyze the consistency of bulk and boundary conditions during relaxation.
  • To determine the validity of surface viscosity models for different timescales.

Main Methods:

  • Linearized differential equations for slab-shaped nematic liquid crystal samples.
  • Analysis of bulk and boundary conditions for time derivatives.
  • Examination of relaxation dynamics using a diffusion equation with surface viscosity.

Main Results:

  • An apparent inconsistency in initial time derivatives is resolved by considering discontinuous field removal.
  • Bulk and dynamical boundary conditions yield identical time derivatives for the nematic director after the switching time.
  • The diffusion equation with surface viscosity is valid for analyzing relaxation at times exceeding the deforming field's switching time.

Conclusions:

  • Localized surface viscosity is a key factor in the slow dynamics of nematic liquid crystals.
  • The concept provides a valid framework for describing relaxation processes under specific conditions.
  • Accurate modeling requires consideration of the timescale relative to the deforming field's switching time.