The shear viscosity is a transport coefficient for momentum in inhomogeneous flows. This transport coefficient, which is widely used to describe both plasmas and fluids, relates two hydrodynamic quantities: shear stress and shear rate. The shear stress Pxy is the off-diagonal element of a pressure tensor, and the shear rate γ is the transverse gradient of the flow velocity u. For a flow in the y direction,
γ=∂uy∂x.
(1)The shear viscosity η relates these two hydrodynamic quantities through the constitutive relation1
Pxy=−ηγ.
(2)In this paper, we will use Eq. (2) to determine the viscosity with an input of experimental measurements of Pxy and γ.
In a plasma, viscosity arises from Coulomb collisions among individual charged particles. This is so for both weakly and strongly coupled plasmas, where the particles in a strongly coupled plasma have an interparticle potential energy that is larger than the thermal kinetic energy. There is a particular interest in viscosity of strongly coupled plasmas2,3 because they are dominated by Coulomb collisions.
Among the many types of strongly coupled plasmas, one that is especially well suited for experiments is the dusty plasma.4–8 It consists of three familiar components of a
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The temperature dependence of viscosity can be very strong; for example, in motor oil, η can diminish ten-fold with only a 10% increase in the absolute temperature. Therefore, if temperature is not uniform but varies with position in a flow, one cannot obtain a single value for its viscosity. The other dependence of viscosity, on shear rate, is a non-Newtonian property of some fluids; this effect is called “shear thinning” if η diminishes with increasing γ.31 Shear thinning can be avoided in an experiment by applying a small shear stress, so that conditions are relatively close to
The complete experimental procedure is available in the General Chemistry Laboratory Manual for CSU Bakersfield, CHEM 213, pages 20-22, 24-25. Experimental data are recorded on the attached data pages.
They just forgot to mention the other effects of fluids in nature. “The influence of the fluid on a body moving through it depends not only on the body’s velocity but also on the velocity of the fluid,” this is called relative velocity ( ). The relative velocity of a body in a fluid has an effect on the magnitude of the acting forces. For example, as a long distance runner is running into a head wind, the force of the fluid is very strong. If the runner is running with the help of a tail wind, the current’s force is reduced and may even be unnoticeable.
The viscosity of the corn syrup, measured in seconds it takes for an iron ball to move downwards in the fluid.
The cell plasma membrane, a bilayer structure composed mainly of phospholipids, is characterized by its fluidity. Membrane fluidity, as well as being affected by lipid and protein composition and temperature (Purdy et al. 2005), is regulated by its cholesterol concentration (Harby 2001, McLaurin 2002). Cholesterol is a special type of lipid, known as a steroid, formed by a polar OH headgroup and a single hydrocarbon tail (Wikipedia 2005, Diwan 2005). Like its fellow membrane lipids, cholesterol arranges itself in the same direction; its polar head is lined up with the polar headgroups of the phospholipid molecules (Spurger 2002). The stiffening and decreasing permeability of the bilayer that results from including cholesterol occurs due to its placement; the short, rigid molecules fit neatly into the gaps between phospholipids left due to the bends in their hydrocarbon tails (Alberts et al. 2004). Increased fluidity of the bilayer is a result of these bends or kinks affecting how closely the phospholipids can pack together (Alberts et al. 2004). Consequently, adding cholesterol molecules into the gaps between them disrupts the close packing of the phospholipids, resulting in the decreased membrane fluidity (Yehuda et al. 2002).
Plasma is referred to as the fourth state of matter, next to solids, liquids, and gases. The term ‘Plasma’ was first employed by Lewi Tonks and Irving Langmuir (LANGMUIR, 1928), to define this fourth state of matter which is partially or wholly ionized state of gas. The change of phase from solid to liquid and further to gas occurs as we increase the energy input likewise increasing the energy input beyond a certain level in gas state causes ionization of molecules which yield the plasma state (Luo et al., 1998). A gas consists of freely moving atoms and/or molecules and these particles are electrically neutral. Plasma is a gas of which a fraction of its constituents are no longer electrically neutr...
Polman, H., Orobio De Castro, B. & Van Aken, M. A.G. (2008). Experimental Study of the
The performance curves based on the ethylene glycol solution will be compared to those developed using water as the base to examine the effect, if any, the viscosity and density of the liquid has on the pump.
Elasticity is one of the most important theories in economics and it is a measure of responsiveness (Baker, 2006)i. There are mainly two types of elasticity, the elasticity of demand which includes price elasticity of demand, income elasticity of demand, and cross elasticity of demand as well as elasticity of supply (McConnell, Brue, & Flynn, 2009)ii. The degree to which a demand or supply curve reacts to a change in price is the curve's elasticity (Lingham, 2009)iii. Elasticity varies among products because some products may be more essential to the consumer.
1 David Halliday, Robert Resnick, and Jearl Walker, Fundamentals of Physics, Extended, 5th ed. (NewYork:Wiley, 1997) 361
On a more scientific note I am interested in mechanics of fluids. This interest was enforced last year when I had the opportunity to attend a lecture on fluid mechanics at P&G. At the conference I greatly expanded my knowledge regarding the physical aspect of fluids and their properties. In last year's AS course we have met a topic in this field. I will be applying ideas and knowledge gathered from last year for this investigation.
Serway, Raymond A, and Robert J Beichner. Physics: For Scientists and Engineers. United States of
Mann, M., 2013. Mind Action Series Physical Sciences 12 Textbook and Workbook. Sanlamhof: Allcopy Publishers.
There are three main variables that determine whether a liquid will posses capillary action. (Davis, 1995)
Schultz, James. "Force Fields and 'Plasma' Shields Get Closer to Reality." Technology 25 July 2000: 20 pars. Web. 25 Oct. 2010. .
2) Fundamentals of Physics Extended: Fifth Edition. David Hanley, Robert Resnick, Jearl Walker. Published by John Wiley & Sons, Inc, New York, Chichester, Brisbane, Toronto, Singapore. 1997.