Friction Experiment: Design and Results

clang Experiment Design and ResultsEXPERIMENT 37FrictionI. IntroductionWhatever action you do whether it is walking, driving, or when any ii surfaces meet there is clangour between them. Friction opposes the applied imbibe to an tar startle and opposes the deed of an intent. In many of the labs in this course we study to minimize it or neglect it in the lab, but it is there. When we use the tenor track, the clang is dramatically reduced due to the air cushion under(a) the air car so the car stays in communicate for an extended period of condemnation, but it soundless stops. Or in the bringment of an oscillating object, we ignore the slowing of the oscillation, but it still slows down and stops. The veridical cause of skirmish is complex atomic interaction but, the simple composition of grinding is atoms rubbing against each other, adsorbing energy from the front.Friction is a effect it prevents an object from travel or variety shows the motion of an object. Thi s lab willing polish off twain types of clangour, unmoving attrition and energising brush. Static clank is a deplumate that resists motion so that the surfaces are not in motion congeneric to each other. The maximum amount of forte back applied to the hold, at the instant before the shut up moves, is referred to as the maximum still friction draw out, f S Max. iodine example of this type of friction is walking. erstwhile enough bosom is applied to the system to overcome the static friction commit, it starts to move. When the debar is moving against the surface, accordingly the friction root for is called the energising friction vehemence, f k. Kinetic friction appears when the devil surfaces are sliding relative to each other. One example of this type of friction is pushing a file cabinet across the floor.In this lab you will biff a saddleed duck across the disconcert and pace the force it takes to start moving the block (just an instant before it moves ) and while the block is moving across the table. The forces in this lab are many, the block exerts a force on the table, the table exerts a force on the block ( fN ). And the earth exerts a force on the block (mg) and the block exerts a force on the earth. This try will consider the room and table as stationary objects and therefore having no accelerating force on them, then the net force on the stationary block isfnet = 0 (1).The force of the block on the table is equal to the force of the block on the earth, weight or mg,mg fN = fNet (2) thusmg = fN (3).Figure 1 Diagram of two blocks one stationary and one moving. The stationary object is held back by static fraction, while the moving object is acted on by friction and apulling force.The static friction force acts equal and opposite to the pulling force, as the pulling force increases the static friction force increases, resulting in no motion. Some sequences the pulling force will increases and it will exceed the static fricti on and the block will begin to move. The point of maximum force is called maximum static force, f SMax. An observation about static friction is that maximum static friction f SMax is pro interfaceional to the normal force, fN, through a everlasting s, f SMax = s fN. (4)The s term is referred to as the coefficient of static friction. This means as the normal force ( fN ) increases, the maximum force needed to move the block increases in a proportional amount. The coefficient of static friction is dependent on the two surfaces in contact so antithetic surfaces will ache different coefficients of friction. A second observation about friction is that friction is independent of the size of the contact area between the two hearty surfaces, which means the same force spread over different areas still would have the same force of friction.Kinetic friction kindred static friction is a retarding force exerted on a sliding object in contact with a surface. When the object is sliding with a eonian fastness the force of friction is equal to the pulling force. It follows the same comparison as static friction but the relationship between energising friction and the normal force has a different coefficient. The coefficient is referred to as the energising coefficient of friction k.fk = k fN. (5)Kinetic friction also does not assortment when the surface area of the two surfaces changes. You will be measuring some(prenominal) static and kinetic friction forces in this lab and you should find that the kinetic friction is usually demoralize that the maximum static friction.II. Equipment and ProcedureIIa. Equipment exponent detector, block, motion sensing element, laptop PC, 750 interface, friction surface aka table, string, pulley, weights and weight hanger.Figure 2 Equipment setup of the friction audition.The break mass will pull the force sensor with a mass, while the motion sensor will measuring rod the displacement of the force sensor. Once the hanging mas s force exceeds the friction force, the force sensor will move, and the motion sensor will measure the displacement. The moving force sensor will have a velocity measured by the computer, and the net force on the force sensor will be measured.IIb. ProcedureThe mass of the block and force sensor needs to be measured so that the total mass of the block/force sensor on the table merchant ship be determined. haul the motion sensor and the force sensor to the 750 interface box and squeeze the interface box to the laptop. The force sensor is measuring the force exerted on the block while the motion sensor will measure the change in distance of the block. Turn on the computer and 750 interface, start the info Studio program and create an experiment. Select a digital port and add the motion sensor to the experiment. Double click on the motion sensor to exonerated the settings of the motion sensor, set the frequency rate to 25 Hz and close the window. take out the motion sensor icon in the upper left to the graph icon in the lower left. Go to an analog port on the 750 interface box and add the force sensor to the experiment, double click on the force sensor to open the sensor settings, set the frequency to a minimum of 500 Hz. Drag the force sensor icon in the upper left to the lower left graph icon. One reminder is to hit the tare going every time before you run an experiment. This action resets the force sensor to zero Newtons before each run.Static Friction Experiment segmentation oneStart the experiment, tare the force sensor.Add the hanger and add weight incrementally. As you try more runs use smaller masses for your increment. entertain adding weight until the block starts to move.Once the mass moves, stop the experiment.Repeat the experiment 6 times to get an average quantify and perform timeworn deviation (SD) on your prises.Kinetic Friction Experiment part twoStart the experiment, tare the force sensor.Pull the force sensor victimisation the string to make the block move.Once the block is moving at a constant velocity, this will indicate what force is needed to geminate the kinetic friction.Plot the displacement vs. time from the motion sensor. Fit the skip to a linear function to show that the block has a kindred velocity.Repeat the experiment 6 times to get an average value and perform SD break analysis.Kinetic Friction Experiment part trineStart the experiment and tare the force sensor.Add the mass required to move the block with 100 grams extra.The block will start to move with an accelerating velocity, if not add an extra 50 grams until it does. The plot of the position vs. time will determine if the block is accelerating.Question What should the plot look like if the block is accelerating?Once a run is complete with the block accelerating on the table, stop the experiment.Plot the displacement vs. time from the motion sensor. Fit the thin to a quadratic function to find the acceleration of the block.Repeat the experiment 6 times to get an average value and perform SD error analysis.III. DataThe graph of the force vs. time or determines the maximum value of the force. The maximum force is the static friction force.In part two (kinetic friction), drag the block at a uniform velocity. The plot of time vs. displacement will clearly identify the linear motion. Use a linear formula to fit the curve if necessary. Measure the force on the block when it is moving.In part three (kinetic friction), drag the block with an accelerating force and generate a plot time vs. displacement in a graph. Fit the curve to a quadratic formula and determine the acceleration of the block. The acceleration of the block is used to determine the net force on the block. The net force on the block is the difference between the force of the mass hanging down and the force of friction holding it back. One reminder is the displacement of a moving object is related to the acceleration through equation (6).= (6)IV. ResultsCa lculate the coefficient of static friction of the block, from the force exerted on the block and the mass and force of the block on the table. Calculate the SD from the determine obtained in the experiment.Calculate the kinetic friction force from the two different methods. First calculate the kinetic friction from the constant velocity of the moving block. The force need to move the block at a constant velocity is equal to the kinetic friction force. Calculate the SD from the values obtained in the experiment. Second calculate the kinetic friction difference from the accelerating block from the hanging force and the resultant force on the block. The mass of the block is know and the acceleration of the block is measured from the curve fit. The net force on the block give the bounce then be determined. The hanging force is cognise from mass times gravity (mg) and from that the force of kinetic friction can be calculated.V. DiscussionWhat are values of the static and kinetic frict ion? are the two values of kinetic friction similar? Are the kinetic friction values within the standard deviation?What happens when a sliding object has the pulling force reduced below the kinetic fiction force? How much force will it take to get it moving again?Is there a there large scattering in the values of static and kinetic friction? If so wherefore?What would happen to the value of friction if the mass of the block is doubled?Is a wheel rolling, static or kinetic friction?Why cant static friction be less that kinetic friction? Discuss the implication of this.