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If a liquid is more dense than another liquid will it be at the top or the bottom?
In 1851, George Gabriel Stokes derived an expression, now known as Stokes' law, for the frictional force - also called drag force - exerted on spherical objects with very small Reynolds numbers (e.g., very small particles) in a continuous viscous fluid. Stokes' law is derived by solving the Stokes flow limit for small Reynolds numbers of the generally unsolvable Navier-Stokes equations: : where: : :* Fd is the frictional force (in N), :* μ is the fluid's dynamic viscosity (in Pa s), :* Ris the radius of the spherical object (in m), and :* V is the particle's velocity (in m/s). If the particles are falling in the viscous fluid by their own weight due to gravity, then a terminal velocity, also known as the settling velocity, is reached when this frictional force combined with the buoyant force exactly balance the gravitational force. The resulting settling velocity (or terminal velocity) is given by: : where: : :* Vs is the particles' settling velocity (m/s) (vertically downwards if ρp > ρf, upwards if ρp < ρf ), :* g is the gravitational acceleration (m/s2), :* ρp is the mass density of the particles (kg/m3), and :* ρf is the mass density of the fluid (kg/m3). Note that for molecules Stokes' law is used to define their Stokes radius.
Stokes's law is the basis of the falling-sphere viscometer, in which the fluid is stationary in a vertical glass tube. A sphere of known size and density is allowed to descend through the liquid. If correctly selected, it reaches terminal velocity, which can be measured by the time it takes to pass two marks on the tube. Electronic sensing can be used for opaque fluids. Knowing the terminal velocity, the size and density of the sphere, and the density of the liquid, Stokes' law can be used to calculate the viscosity of the fluid. A series of steel ball bearings of different diameter is normally used in the classic experiment to improve the accuracy of the calculation. The school experiment uses glycerine as the fluid, and the technique is used industrially to check the viscosity of fluids used in processes. It includes many different oils, and polymer liquids such as solutions. The same theory can be used to explain why small water droplets (or ice crystals) can remain suspended in air (as clouds) until they grow to a critical size and start falling as rain (or snow and hail). Similar use of the equation can be made in the settlement of fine particles in water or other fluids. The CGS unit of kinematic viscosity was named "stokes" after his work.
Measurement Laboratory No. 3
EGR 101
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where m
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5) Using Stokes Law determine the viscosity of the unknown fluid by using the
average velocities of each of the two different size spheres.
7. Concluding Questions
1) In Part I, Step 8, what is the value of the Reynold's Number, and using this value is
Stokes' Law valid? Why, or why not?
2) In Part II, Step 4, were there any difficulties in measuring the fall times of the brass
spheres? Would increasing the diameter of the brass sphere make the problem
worse or better?
3) In Part III, Step 4, how did your predicted fall times compare to measured fall
times? What were the possible sources of error if any that occurred?
4) Given your calculated density and viscosity of your unknown fluid in Part IV,
confirm your findings with the lab TA to identify your unknown fluid. Who did
your results compare to the data from the TA?
5) In the lab manual there is a formula listed for Stokes Law that contains a correction
factor relating the diameter of the sphere and the diameter of the graduated
cylinder. Measure the diameter of the graduated cylinder and determine the
corrected fall times for the two different size spheres in Part IV?
6) Was there a significant difference between the corrected values for fall times and
the non-corrected values? How much did the diameter of the graduated cylinder
influence the fall time of the sphere?
What else can I help you with?
What would happen if you have 2 liquids with different densities in the same container?
The liquid with higher density will settle at the bottom, while the one with lower density will float on top due to the principle of buoyancy. The liquids will not mix and will form distinct layers based on their densities.
How do you tell which one is the densest liquid if you pour three liquids into a beaker?
To identify a liquid that is most dense it would be at the bottom of a container because the the most dense sinks while the least dense float at the top. example. if your teacher gave you an experiment to do and she gave you olive oil,dish soap,and color water. and you put those liquid in a see through container the least dense is the alcohol because that has the least density in it, and the most dense is soap. so if you put a couple of liquids in a container the most dense will appear at the bottom while the least will be on top. hope this help:)
What is more dense water vapor liquid water or ice?
Ice water is more dense than warm water.
What is a liquid more dense than maple syrup?
guessing mercury
Can you describe the density changes between the two substances that a lava lamp contains?
The lava lamp contains two substances: the lava (wax) and the liquid (usually a type of oil). The lava is denser than the liquid when cold, causing it to sink to the bottom of the lamp. When the lamp is turned on and the wax heats up, it becomes less dense than the liquid, causing it to rise to the top. This continuous cycle of heating and cooling creates the lava lamp's mesmerizing motion.
Why would a liquid go over another?
one liquid would be more dense (bottom liquid) and one would be less dense (top liquid) as oil would go on top of water no matter what unless shaken because oil is less dense than water as water has a density of 1
Which one will be on bottom a density of 1 or 1.3?
The more dense liquid will be on the bottom in this case the one that is 1.3
What happens when you put a less dense soild and a more dense liquid together?
solid will be settling at the bottom because liquid can not be denser than solid due to their arrangements of their molecules.
How do you tell which liquid will float on top of the other?
This is found out by knowing the densities of the liquids in question. The liquid with the smaller density will always be on top, while the liquid with the higher density will be at the bottom.
How can you tell if one liquid is more dense than another?
You can tell if one liquid is more dense than another by comparing their densities. The denser liquid will have a greater mass per unit volume than the less dense liquid. One common way to compare densities is by observing which liquid sinks and which floats when they are layered on top of each other in a container.
How will you describe condenser?
Condenser use to condense the liquid for e.g: seperation of an emulsion by condensing the liquid & form different layer of oil & water &more dense liquid willlie at the bottom by that we can seperate the liquid. ;-)
A substance floats or sinks in another because of its relative?
density. If the substance is less dense than the liquid it is placed in, it will float. If the substance is more dense than the liquid, it will sink.
What would happen if you have 2 liquids with different densities in the same container?
The liquid with higher density will settle at the bottom, while the one with lower density will float on top due to the principle of buoyancy. The liquids will not mix and will form distinct layers based on their densities.
Can a solid be more dense than a liquid?
Yes, a solid can be more dense than a liquid. Density is defined as mass per unit volume, so a solid with a higher mass per unit volume than a liquid will be more dense. An example is comparing ice (solid) to water (liquid), where ice is more dense than liquid water.
Is liquid water less dense than ice cubes?
No. Liquid water is more dense. This is why ice cubes float on liquid water.
Is an ice cube more dense or less dense than liquid water?
Less dense. For most substances, the solid form is more dense than the liquid form; water is a notable exception.Less dense. For most substances, the solid form is more dense than the liquid form; water is a notable exception.Less dense. For most substances, the solid form is more dense than the liquid form; water is a notable exception.Less dense. For most substances, the solid form is more dense than the liquid form; water is a notable exception.
Is Liquid water less dense or more dense?
Liquid water is more dense than ICE , and More dense than water vapour(steam). Liquid water is at its most dense at 2 oC. Water on freezing to ice expands by about 10% of its volume. This is because of the lattice arrangement of water molecules in ice., which does not occur in liquid water., Hence ice floats on water. (icebergs).
