Introduction and Literature Review:
Friction is a force which opposes the movement of an object due to two surfaces being in contact with each other. Friction is affected by surface material (roughness), the surface area in contact and the mass of the object. The following investigation is to prove that friction will increase with increasing texture/’roughness’ of the surface material.
Surface texture and friction is dependent on the nature of the intermolecular forces present in the surfaces (R.Nave, n.d). When objects slide past each other intermolecular forces decrease , therfore decreasing friction. This is due to there being less molecules in contact with each other, the more contact there is the more friction there will be(Mann, 2013). All substances have different molecule sizes and so friction differs between different substances.
The surface texture is a factor in the maximum static friction and kinetic friction of an object. This is due to surface texture opposing the applied force; once the forces opposing motion are overcome you reach the maximum static friction (Mann, 2013).If the object is pulled with a consant force after this kinetic friction can be measure, this value will decrease over time (R.Nave, n.d.). The formula derived from the information is that maximum static friction from this is fs(max)=µsN and for kinetic friction it is fk=µkN .(Mann, 2013)
Many studies have been done on the effects of surface texture and its affect on friction.When 2 extremaly smooth objects slide past each other the friction between these objects is so great they are welded togethor . This is used in metal cutting to weld metals togethor without having to melt them first. (CHEN, Ping , 1988). By changing surface texture , you ...
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...ted and applied more/less pressure on the sandpaper which effects how many particles are in contact .
In conclusion when surface texture is increased the force needed to move the object at a constant speed is increased. This proves the hypothesis made earlier in the practical that as surface texture increases so will friction increase.
Bibliography
Chen, P., 1988. Study of cold welding caused by friction in metal cutting. Wear, 121(2), pp. 173-182.
Mann, M., 2013. Mind Action Series : Physical Science Textbook and Workbook Grade 11 NCAPS. 2 ed. Cape Town: All Copy Publisher.
R.Nave, n.d. Hyper Physics. [Online]
Available at: http://hyperphysics.phy-astr.gsu.edu/hbase/frict.html
[Accessed 14 May 2014].
Ulrika Pettersson, S. J., 2003. Influence of surface texture on boundary lubricated sliding contacts. Tribology International, 36(11), pp. 857-864.
It would make sense to assume that this smooth, undisturbed air would create the least amount of resistance due to friction. The golf ball seemingly defies this theory by traveling farther with its disruptive surface texture that creates the second characteristic, turbulent flow. Turbulent flow is a flow that is disturbed and creates whirlpool like features. The turbulent air actually lessens the difference in velocity of the air layer that is extremely close to the ball compared to the rest of the air and so lessens the friction acting on the ball. Drag is a major contributor to how an object travels through fluid/air.
The material cause: aspect of the change or movement which is determined by the material that composes the moving or changing thing
6th ed. of the book. Stanford, a.k.a. The Science of Science, 2006. Print.
"Welding Processes, Welding Faults, Defects & Discontinuities For NDT Technicians Part 3." Hera.org. Hera, n.d. Web. 15 Mar. 2014. .
I have learned quite a lot while constructing my mousetrap car. For example i learned that the friction that is active while the mousetrap car is in motion is rolling and static. Rolling friction occurs when an object rolls over a surface, in my case the CDs are rolling on the floor causing the car to move. Static friction occurs when one solid surface slides over another, for example my solid car sliding over a solid surface.Fortunately i didn't have very much problems related to friction.
The application of force on an object causes an acceleration of that object. Yet, force is not the only factor in the movement, or acceleration of an object. The two main influences on the acceleration of an object are net force and mass. For example, net force is directly proportional to acceleration while mass is inversely proportional to acceleration. Other factors such as the friction, air or fluid resistance, and pressure effect the acceleration as well. All of these factors do not work against or in accordance with acceleration in the same way. Friction works in opposition to acceleration. Friction involves two objects that are in direct contact with on another but are moving in different directions. Involved with friction is air and fluid resistance. Fluid resistance, such as liquids or gases, focuses on when the object is moving in the opposite direction of a fluid flow or through a dense area of fluid. Air resistance involves movement through the air. The most noticeable effect of air resistance is when and object travels into a strong breeze or wind. And finally pressure, pressure refers to an applied force. With pressure you will find that the overall weight of and object doesn’t change no matter how you stand or lay it but you will feel more pressure from that same object depending on the force compared to the amount of surface area. The weight of the object
Kinematics unlike Newton’s three laws is the study of the motion of objects. The “Kinematic Equations” all have four variables.These equations can help us understand and predict an object’s motion. The four equations use the following variables; displacement of the object, the time the object was moving, the acceleration of the object, the initial velocity of the object and the final velocity of the object. While Newton’s three laws have co-operated to help create and improve the study of
Mann, M., 2013. Mind Action Series Physical Sciences 12 Textbook and Workbook. Sanlamhof: Allcopy Publishers.
Abrasive technique is the mechanical technique to make the surface ready for printing or bonding. It serves only to increase. It increases the surface area of the material by "roughening" the exposed areas prior to coating, printing or adhesive bonding. Mechanical abrasion can be achieved by dry blasting, wet blasting or hand/machine blasting. To remove particulates or residues, a sol vent wash usual l y follows mechanical abrasion. In many cases, the spent abrasive materials fall under the classification of hazardous substances and must be disposed of accordingly.
Welding is an art, science, and high paying career all in one. Welding is the most effective way to join two pieces of metal, it is the only way to join them so they act as one. Numerous things in our daily lives has been welded from coffeepots to skyscrapers. Welding can be done almost anywhere outdoors, indoors, underwater, and even space (“Welding Basics”). It is practically
Sasaki, Tomoaki. "Study for TIG-MIG Hybrid Welding Process - Springer." Linked.springer.com. Springer, 01 Jan. 2014. Web. 28 Apr. 2014.
?Robotics will boost quality and transfer efficiency levels.? Coatings (Jul.-Aug. 1991): 66 InfoTrac. Online. Nov. 2002. .
Fluid motion over the objects surface is inducted by buoyancy effects that have resulted from the change in density. This change is due to the differences in temperature of the fluid as heat energy is transferred.
Experimental Mechanics involves the experimental investigations of the static and dynamic response of structures and machines, and in the development of improved techniques to obtain and analyze experimental data.