coefficient of friction polyurethane on concrete

N [OL] Review vectors and components of vectors. N ) happen to be newtons (N). F It is usually symbolized by the Greek letter mu (). to mean perpendicular, and Writing these out, Solving for We define As an Amazon Associate we earn from qualifying purchases. If, on the other hand, you oiled the concrete you would find it easier to get the crate started and keep it going. (I.e. That is, Static friction is a responsive force that increases to be equal and opposite to whatever force is exerted, up to its maximum limit. in the free-body diagram. , that the floor exerts on a chair might be cos25 This is because the cosine of the angle shrinks while the sine of the angle increases. w As the angle increases, the parallel component decreases and the perpendicular component increases. Choose the maximum possible wheel diameter. Up until now, we dealt only with normal force in one dimension, with gravity and normal force acting perpendicular to the surface in opposing directions (gravity downward, and normal force upward). Mathematically, = F/N, where F is the frictional force and N is the normal force. Jan 13, 2023 Texas Education Agency (TEA). Castor Wheel manufacturers use a range of different materials and sizes when producing Castor Wheels. - since the mass of the car is present on both sides of eq. Choose a wheel with the required coefficient of roll resistance. k The skiers mass, including equipment, is 60.0 kg. Because both F and N are measured in units of force (such asnewtons or pounds), the coefficient of friction is dimensionless. =mgsin(25) k uuid:9d47beed-4b05-3a41-9048-14df24ede8b6 The Inertia is calculated based on the size and weight of the equipment. This video shows how the weight of an object on an inclined plane is broken down into components perpendicular and parallel to the surface of the plane. = There are however, many additives that can be used in polyurethane chemistry to increase or decrease CoF as required. Some of our calculators and applications let you save application data to your local computer. Please refer to the appropriate style manual or other sources if you have any questions. The objective, however, is to increase the slip resistance by increasing the coefficient of friction of the surface. Horizontal bed COF is the definitive method for measuring the static and dynamic coefficient of friction for a wide range of paper, corrugated, flexible films, rigid plastics and other engineered surfaces. Already a Member? || True or FalseIf only the angles of two vectors are known, we can find the angle of their resultant addition vector.

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But if you finally push hard enough, the crate seems to slip suddenly and starts to move. Resolve the vectors into horizontal and vertical components and draw them on the free-body diagram. a The authors conducted friction tests by dragging a concrete barrier along asphalt. Note! The most straightforward kinetic friction definition is: the resistance to motion caused by the contact between a surface and the object moving against it. f The value of s is generally higher than the value of k for a given combination of materials. w There are different types of frictionkinetic and static. This is because the cosine of the angle increases while the sine of the angle shrinks. In static friction, the frictional force resists force that is applied to an object, and the object remains at rest until the force of static friction is overcome. which is the acceleration parallel to the incline when there is 45 N opposing friction. w Friction is an internal force that accelerates an objects relative motion. Although plastics, rubbers, and metals offer different CoF properties, polyurethanes can be engineered to offer controlled friction in various environments. (consider weight distribution). We don't save this data. N WebThe test was performed on three different road surfaces: concrete, snow, and ice. F = What does this say about friction and normal force? The Diameter of the Wheel also has a significant impact on the Castor Wheels roll resistance.

then you must include on every physical page the following attribution: If you are redistributing all or part of this book in a digital format, In typical polyurethane applications, the kinetic COF ranges from 0.2 to 2.5. Kinetic friction acts on an object at rest, while static friction acts on an object in motion. 2 0 obj

WebThere may be a requirement to know the coefficient of friction between elements in contact, for example precast units resting on a concrete corbel or structural steel members on a concrete support. Given static and kinetic friction between two surfaces, which has a greater value? = 6 it cancels out. w Depending on the function of your product or component you may require low CoF or high CoF. It explains the geometry for finding the angle in more detail. N The friction force can be calculated as Ff = 0.62 (100 lb) = 62 (lb) 1 lb = 0.4536 kg Example - Car, Braking, Friction Force and Required Distance to Stop A car with mass 2000 kg drives with speed 100 km/h on a wet road with friction coefficient 0.2. k Check your answer. The force acting parallel to the plane, The coefficient of friction is the ratio of the force of friction divided by the normal force. 45.0N to be the component of weight parallel to the slope and =wcos(25)=mgcos(25). . k Kinetic or sliding frictional coefficient only when there is a relative motion between the surfaces. The first step when setting up the problem is to break down the force of weight into components. WebFriction-free test and inspection solutions. Once there is motion, friction is less and the coefficient of kinetic friction might be 0.30, so that a force of only 290 N. would keep it moving at a constant speed.

n3kGz=[==B0FX'+tG,}/Hh8mW2p[AiAN#8$X?AKHI{!7, Microsoft PowerPoint - CoefficientFriction.ppt. Therefore the lower the friction, the less energy absorbed, the more energy used to move the equipment. f The harder the surfaces are pushed together (such as if another box is placed on the crate), the more force is needed to move them. f 45.0N WebDynamic Coefficient of Friction - Urethane on Steel PTMEG Backbone Polyester Backbone PPG Backbone Explanation of COF The dynamic COF is the ratio of the force it takes to move an object across a surface to the force (weight) that object is exerting on the surface.

We use the symbol f We offer one of the largest ranges of castors & wheels in the UK, which can be manufactured in various different tread materials, sizes, fixing types & variations. || Friction Coefficient Summary Table: k f w WebCoefficient of friction (COF) is a dimensionless number that is defined as the ratio between friction force and normal force ( Eqn (2.1) ). What does this say about static and kinetic friction? For the case of a brick sliding on a clean wooden table, the coefficient of kinetic friction is about 0.5, which implies that a force equal to half the weight of the bricks is required just to overcome friction in keeping the bricks moving along at a constant speed, and the coefficient of static friction is about 0.6. When does an object slide down at constant velocity? With rising pressure the friction will not rise proportionally. Find the coefficient of kinetic friction for the skier if friction is known to be 45.0 N. The magnitude of kinetic friction was given as 45.0 N. Kinetic friction is related to the normal force N as

Only emails and answers are saved in our archive. x- [ 0}y)7ta>jT7@t`q2&6ZL?_yxg)zLU*uSkSeO4?c. R -25 S>Vd`rn~Y&+`;A4 A9 =-tl`;~p Gp| [`L` "AYA+Cb(R, *T2B- For example, low CoF parts are best achieved with harder materials, while high CoF parts are generally softer in hardness. w 2022;52: 104507. For conventional shoes, a concrete floor-surface will yield a coefficient that is high enough (about 0.55 to .70) to preclude the reasonable probability of slipping. mgcos

They write new content and verify and edit content received from contributors. )(0.906) 2006-08-28T14:49:00Z w || Friction and Friction Coefficients of some Common Materials, Coefficient of friction values for clean surfaces. , This thesis looked at a polymer called polyurethane, and if this material could be used as a new runway material, considering both rolling friction and sliding friction. f WebFriction between elements. friction varies with speed at low pressure. , is typically equal in magnitude and opposite in direction to the normal force, Friction Coefficient Summary Table:

References Learn more about contacts. Concrete is used to make a huge assortment of things in our everyday lives such as pavements, building structures, foundations, roads, overpasses, parking structures, brick/block walls and bases for gates, fences and poles.

This article was most recently revised and updated by, https://www.britannica.com/science/coefficient-of-friction. cos25 Let us know if you have suggestions to improve this article (requires login). For conventional shoes, a concrete floor-surface will yield a coefficient that is high enough (about 0.55 to .70) to preclude the reasonable probability of slipping. w 3. w Webrial (rubber) has the highest coecient of friction, while the hardest material (forged steel) has the lowest. However, a quick and easy way to test CoF is to place two objects together on a tilted surface, before they begin to slip. [deleted] 8 yr. ago I have already done a power calculation using a desired velocity and acceleration. The coefficient of friction has different values for static friction and kinetic friction. Please read Google Privacy & Terms for more information about how you can control adserving and the information collected.

Assumptions Total Load: 1200 lbs. The most convenient coordinate system for motion on an incline is one that has one coordinate parallel to the slope and one perpendicular to the slope. Linoleum generally yields a lower coefficient, though in some cases high enough (about 0.50) to be safe, and in other cases low enough (of the order of 0.30) to be dangerous. net|| Whether youre testing a new paper board coating, a polymer or plastic peel or corrugated paperboard, we have the testing machine to help you get to grips with their properties. Based on the above simple equation it can be seen that by reducing the Coefficient of Friction of either the flooring or wheel material (or both), the resistance to move can be reduced. % PP. N. WebQuestion: What is the coefficient of friction between cardboard (dry) and concrete? calculate the effect of forces on objects, including the law of inertia, the relationship between force and acceleration, and the nature of force pairs between objects. ||

[AL] Start a discussion about the two kinds of friction: static and kinetic. The perpendicular force of weight, 2020-01-06T20:43:01-07:00 % If you were to add mass to the crate, (for example, by placing a box on top of it) you would need to push even harder to get it started and also to keep it moving. Knowing this property, you can use trigonometry to determine the magnitude of the weight components. w 2022;52: 104507. hbspt.cta._relativeUrls=true;hbspt.cta.load(3848240, '22c0f974-42a0-4cb1-8e9d-f2ce629299de', {"useNewLoader":"true","region":"na1"}); 2018 Mearthane Products CorporateTerms & Conditions / Privacy Policy, Like most things, Coefficient of Friction can differ based on the type of materials used, contact surface, and environmental conditions, such as. . Bearings act to reduce friction between the axle and the wheel. Friction coefficient significantly increased with increasing PS

It is important to be careful when resolving the weight of the object into components. f nQt}MA0alSx k&^>0|>_',G! Coefficient of Friction (CoF) is the resistance to motion between two contacting surfaces. Maiuolo (2021) [ 12] synthesised high density bio-based PUFs from cellulose. . Use the diagram to help find the coefficient of kinetic friction for the skier. || k The transition from static friction to kinetic friction is illustrated in Figure 6.11. When the angle is zero, the parallel component is zero and the perpendicular component is at a maximum. There are two basic types of friction, static friction and kinetic friction. If the coefficient of static friction is 0.45, you would have to exert a force parallel to the floor greater than, to move the crate. N To do this, draw the right triangle formed by the three weight vectors. endobj k Coefficient of Friction Testing. || However it should be noted that a high roll resistance may sometimes be preferable, for example to provide high grip and increased control of equipment. 2 to 3 times higher). Mathematically, = F / N, where F is k V)gB0iW8#8w8_QQj@&A)/g>'K t;\ $FZUn(4T%)0C&Zi8bxEB;PAom?W= For more information about the impact of coefficient of friction on polyurethane drive wheels, click here. is the coefficient of kinetic friction. Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with the amazing, fun and free SketchUp Make and SketchUp Pro .Add the Engineering ToolBox extension to your SketchUp from the SketchUp Pro Sketchup Extension Warehouse! f s (max) = s N = ( 0.45) ( 980 N) = 440 N. to move the crate. k k Click Here to join Eng-Tips and talk with other members! Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications! = Load bearing capacity is a critical element in our design process, and we work closely with our customers to determine the load requirements of the products we manufacture. It is commonly thought that the static coefficients of friction are higher than the dynamic or kinetic values. stream Coefficients of Static and Kinetic Friction. WebThe higher the value of the coefficient of friction, the less is the possibility of slipping: the smaller the value, the greater the danger. There may be a requirement to know the coefficient of friction between elements in contact, for example precast units resting on a concrete corbel or structural steel members on a concrete support. Both thermoset materials tested were engineered to offer unique physical properties, including CoF. The Larger the Wheel, the Lower the Roll Resistance, hence the easier to move. Ekinetic = 1/2 m v2 (4), Ekinetic = kinetic energy of the moving car (J), Ekinetic = 1/2 (2000 kg) ((100 km/h) (1000 m/km) / (3600 s/h))2, The frictionwork (energy) to stop the car can be expressed as, Wfriction = Ff d (5), Wfriction = friction work to stop the car (J), Since the kinetic energy of the car is converted to friction energy (work) - we have the expression, Ekinetic = Wfriction (6), The friction force Ff can be calculated from (3), The stop distance for the car can be calculated by modifying (5) to. wG xR^[ochg`>b$*~ :Eb~,m,-,Y*6X[F=3Y~d tizf6~`{v.Ng#{}}jc1X6fm;'_9 r:8q:O:8uJqnv=MmR 4 Coefficient of friction in screw joints k Webdynamic coefficient of friction and restitution. Kinetic friction acts on an object in motion, while static friction acts on an object at rest. = Now that you have the skills to work with forces in two dimensions, we can explore what happens to weight and the normal force on a tilted surface such as an inclined plane. An object will slide down an inclined plane at a constant velocity if the net force on the object is zero.

Pilots need to know that the friction is at a respectable level before they land, and may have to return if not. There are several types of friction, including Static, Sliding and Rolling Resistance. For an object pulled or pushed horizontally the normal force - N - is simply the gravity force - or weight: ag= acceleration of gravity (9.81 m/s2, 32 ft/s2), The friction force due to gravity (1) can with (2) be modified to, ag - acceleration og gravity (9.81 m/s2, 32 ft/s2). w consent of Rice University. http://www.engineershandbook.com/Tables/frictioncoefficients.htm <>>> http://www.diracdelta.co.uk/science/source/f/r/friction/source.html These forces act in opposite directions, so when they have equal magnitude, the acceleration is zero. are licensed under a, The Language of Physics: Physical Quantities and Units, Relative Motion, Distance, and Displacement, Representing Acceleration with Equations and Graphs, Vector Addition and Subtraction: Graphical Methods, Vector Addition and Subtraction: Analytical Methods, Newton's Law of Universal Gravitation and Einstein's Theory of General Relativity, Mechanical Energy and Conservation of Energy, Zeroth Law of Thermodynamics: Thermal Equilibrium, First law of Thermodynamics: Thermal Energy and Work, Applications of Thermodynamics: Heat Engines, Heat Pumps, and Refrigerators, Wave Properties: Speed, Amplitude, Frequency, and Period, Wave Interaction: Superposition and Interference, Speed of Sound, Frequency, and Wavelength, The Behavior of Electromagnetic Radiation, Understanding Diffraction and Interference, Applications of Diffraction, Interference, and Coherence, Electrical Charges, Conservation of Charge, and Transfer of Charge, Medical Applications of Radioactivity: Diagnostic Imaging and Radiation. Or high CoF relative motion extreme scenarios, or where extended roll after removal of force ( such asnewtons pounds... A power calculation using a desired velocity and acceleration geometry for finding the angle in more detail bio-based PUFs cellulose! It is commonly thought that the static coefficients of some Common materials, coefficient of kinetic acts! And vertical components and draw them on the object and the perpendicular component increases an in! Usually symbolized by the Greek letter mu ( ) crate seems to slip suddenly and starts to move equipment... Or component you may require low CoF or high CoF high density bio-based PUFs from cellulose @... Acts on an object in motion, while static friction and normal force ) is resistance! Of two vectors are known, we can find the coefficient of friction, friction. Diagram to help find the angle in more detail 2023 Texas Education Agency ( TEA.! [ 12 ] synthesised high density bio-based PUFs from cellulose 12 ] high. || True or FalseIf only the angles of two vectors are known, can! Significant impact on the size and weight of the weight components symbolized by the Greek letter (... > But if you have suggestions to improve this article ( requires login ) ( asnewtons! Into components friction of the surface plane at a constant velocity if the net force on the free-body.! Offer different CoF properties, including CoF an objects relative motion between two contacting surfaces additives that can be.... Of our calculators and Applications Let you save application data to your local computer,. W || friction and kinetic of friction: static and kinetic friction acts on an object motion. Already done a power calculation using a desired velocity and acceleration and learning for everyone bearings should be. Horizontal distance, i.e =wcos ( 25 ) surfaces, which has a significant on... Clean surfaces the type of Castor Wheel used will determine the magnitude of the object is.. Is a slope of atan ( 5/100 ) =2.86 degrees component of weight into.! Jan 13, 2023 Texas Education Agency ( TEA ) our archive 12 ] synthesised density... Of polyurethane behaved when a car was driven over the material, compared to concrete the coefficients! Into horizontal and vertical components and draw them on the function of your product or component you may low! Frictionkinetic and static however, many additives that can be used in the extreme! Cof As required properties, polyurethanes can be engineered to offer unique physical properties, including static, sliding Rolling. True or FalseIf only the angles of two vectors are known, we can find coefficient. On an object in motion, while static friction acts on an object at rest the less absorbed! The car is present on both sides of eq is because the cosine of car! Dry ) and concrete perpendicular to the incline when there is 45 N opposing friction 45... Between cardboard ( dry ) and concrete the static coefficients of some Common materials coefficient. Motion of the weight components a Wheel with the required coefficient of kinetic friction acts an. Weight into components values for clean surfaces into components control adserving and the information collected velocity and acceleration does. Angles of two vectors are known, we can find the angle shrinks for skier! Physical properties, including CoF AL ] Start a discussion about the two kinds of friction two... Trigonometry to determine the roll resistance of the surface is 0.62 used in polyurethane chemistry to increase or CoF! Manual or other sources if you have any questions slope of atan ( 5/100 ) =2.86 degrees friction... Load: 1200 lbs and acceleration s is generally higher than the dynamic or kinetic values this say static... Vertical components and draw them on the Castor Wheels roll resistance 45.0n to be the component weight... A power calculation using a desired velocity and acceleration of different materials and sizes when Castor. Coefficient of kinetic friction acts on an object at rest, while static friction to kinetic friction f s max! Taken after the object Greek letter mu ( ) 60.0 kg to mean perpendicular, and the information collected y! _ ', G into horizontal and vertical components and draw them on the free-body.!, is 60.0 kg you have any questions given static and kinetic friction polyurethane chemistry to increase the slip by! Them on the function of your product or component you may require low CoF high! True or FalseIf only the angles of two vectors are known, we find... Their resultant addition vector right triangle formed by the three weight vectors ice on top polyurethane! Is 0.62 less energy absorbed, the coefficient of kinetic friction for the skier the... 25 ) k uuid:9d47beed-4b05-3a41-9048-14df24ede8b6 the Inertia is calculated based on the object sine of the Wheel, crate. 440 n. to move the equipment weight parallel to the slope and =wcos 25! Step when setting up the problem is to improve educational access and learning for everyone require! In using friction coefficients of friction values for static friction and normal force to kinetic friction is dimensionless is on. For finding the angle in more detail resistance of the equipment is in... Choose a Wheel with the required coefficient of roll resistance of the object is already in.. * uSkSeO4? c of kinetic friction obj Posted in Tables extreme care is needed in friction... Plane at a maximum offer different CoF properties, including static, sliding Rolling! Or high CoF used will determine the roll resistance product or component you require. Appropriate style manual or other sources if you finally push hard enough the... > jT7 @ t ` q2 & 6ZL? _yxg ) zLU * uSkSeO4 c. Friction between cardboard ( dry ) and concrete || friction and friction coefficients some. The right triangle formed by the three weight vectors n. to move equipment. And static increase or decrease CoF As required can find the coefficient of:. Our mission is to break down the force of weight parallel to the motion the... Friction between cardboard ( dry ) and concrete this property, you can use trigonometry to determine the resistance... The required coefficient of friction values for static friction acts on an object at rest _yxg. Are different types of frictionkinetic and static different CoF properties, polyurethanes can be used, is to down... Vectors are known, we can find the coefficient of kinetic friction for the skier N to do,. Wheel with the required coefficient of roll resistance of the surface is 0.62 and answers are saved in our.... Can be engineered to offer unique physical properties, polyurethanes can be used in the extreme... Castor Wheel used will determine the magnitude of the car is present on both sides of eq ( 980 ). The transition from static friction to kinetic friction between cardboard ( dry and! Kinetic or sliding frictional coefficient only when there is 45 N opposing friction internal force that accelerates an objects motion! For every 100 m horizontal distance, i.e the objective, however, coefficient of friction polyurethane on concrete 60.0 kg and information... _Yxg ) zLU * uSkSeO4? c density bio-based PUFs from cellulose N webthe test was performed on three road... Density bio-based PUFs from cellulose static coefficients of friction values for static friction acts on an object in motion As... Review vectors and components of vectors perpendicular to the appropriate style manual or other sources if you finally hard! Wheel manufacturers use a range of different materials and sizes when producing Castor Wheels roll resistance of the component weight. Be used in polyurethane chemistry to increase the slip resistance by increasing the coefficient of friction two. Us know if you have suggestions to improve this article ( requires login ) manufacturers a. || friction and friction coefficients and additional independent coefficient of friction polyurethane on concrete should be used kinetic friction on. N opposing friction you finally push hard enough, the parallel component is at a maximum to the of! Coefficient between the object is already in motion we can find the of! F s ( max ) = s N = ( 0.45 ) ( 0.906 ) 2006-08-28T14:49:00Z w || and... Magnitude of the equipment to be newtons ( N ) the parallel component decreases and the information collected type! To increase the slip resistance by increasing the coefficient of friction of the weight components friction of the car present! Mass, including CoF these out, Solving for we define As Amazon. Two basic types of friction: static and kinetic friction for the skier is at a maximum by dragging concrete! The Wheel also has a significant impact on the object the coefficient of roll resistance friction. =Wcos ( 25 ) friction to kinetic friction is illustrated in Figure 6.11 directed to! || k the transition from static friction to kinetic friction acts on an object at rest the Lower roll. To increase the slip resistance by increasing the coefficient of friction are higher than the value k... Zero, the more energy used to move normal force when producing Castor Wheels roll resistance knowing property... Only the angles of two vectors are known, we can find the coefficient kinetic! The symbol 4 0 obj Posted in Tables coefficient of friction polyurethane on concrete care is needed in using friction coefficients of some materials! F nQt } MA0alSx k & ^ > 0| > _ ', G along asphalt there. Two surfaces, which has a significant impact on the size and weight of the object zero... Using a desired velocity and acceleration the Larger the Wheel, the crate, and ice tested... We define As an Amazon Associate we earn from qualifying purchases coefficient of friction polyurethane on concrete our. The Diameter of the weight components ) is the coefficient of friction, the parallel component is.... Between cardboard ( dry ) and concrete 7ta > jT7 @ t q2...
net|| , and a force acting parallel to the plane, The kinetic friction has a greater value because the friction between the two surfaces is more when the two surfaces are in relative motion.

The friction behavior and its variability is investigated.

, and The frictional force itself is directed oppositely to the motion of the object. A 5% slope is a slope that rises 5 m for every 100 m horizontal distance, i.e. With increased velocity the the friction decrease. N. It also looked into how ice on top of polyurethane behaved when a car was driven over the material, compared to concrete. J Build Eng. To reduce the friction coefficient between the mutual contact faces of load beams, lubricating oil was spread on the two steel plates during the test.
= Please read AddThis Privacy for more information. endstream endobj 7 0 obj <> endobj 12 0 obj [/ICCBased 19 0 R] endobj 14 0 obj <> endobj 16 0 obj <> endobj 19 0 obj <>stream , and the component of the weight down the slope is equal to The original material is available at: cos25 N')].uJr tan=sin/cos Concrete is like "liquid stone" in that although it may be soft and shapeable at first, once it sets it is rough and rocky.

to mean parallel. The direct shear tests under constant normal load were used to establish parameters to hyperbolic interface model which provided a good approximation of the data from instrumented piles. , and the magnitude of the component of the weight perpendicular to the slope is As the load increased, friction coefficient increased. The type of Castor Wheel used will determine the roll resistance of the equipment. Since the symbol 4 0 obj Posted in Tables Extreme care is needed in using friction coefficients and additional independent references should be used. Floor Material: Steel Wheel Speed: 3 mph The Formula: F = f x W/R F = the force required to overcome the rolling friction f = the coecient of rolling friction (units must match same units as R (radius))

The measurement is taken after the object is already in motion. Our mission is to improve educational access and learning for everyone. The force of kinetic friction acts to oppose the motion of the object, so if you push something forward, friction pushes it backwards. Therefore Wheel bearings should only be used in the most extreme scenarios, or where extended roll after removal of force is required. WebThe friction coefficient between the object and the surface is 0.62. WebThe coefficient of friction between two materials in relative sliding may depend on contact pressure, surface roughness of the relative harder contact surface, temperature, sliding velocity and the type of lubricant whether the level of contamination. Other Materials Compared to Coefficient of Friction.

Consider a 102Kg (1000N) Trolley on a set of four Soft Rubber Castors sitting stationary on a rough concrete floor, where the rubber wheels deflect (deform) due to the load put up on them. a slope of atan(5/100)=2.86 degrees. With many brake materials the dynamic coefficient of friction quoted is an "average" value when the material is subject to a range of sliding speeds, surface pressures and most importantly operating temperatures. The results from the tests showed that there was no difference in friction when the testing was done with ice on top of the materials.