Coefficient of Kinetic Friction

AI Thread Summary
The discussion centers on a lab report involving a hockey puck sliding down a ramp, focusing on kinetic friction. It questions the assumption of constant acceleration, noting that factors like air resistance and ramp imperfections may cause variations in acceleration. The relationship between mass and friction coefficients is clarified, indicating that while mass influences the normal force, it does not affect the coefficient of friction itself since both gravity and friction depend on mass. Sources of error in the experiment include human measurement inaccuracies and external factors like air resistance, which can impact the puck's movement. Overall, careful setup and repeated trials are recommended to minimize these errors for more accurate results.
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I am working on a lab report in which a hockey puck is put on a ramp which is lifted until the puck slides. Displacement, acceleration and time are measured. Can someone help me with the discussion questions? I wanted to be as indepth as possible with my answers, thanks in advance.

1) Assess the assumption that acceleration was constant as the object moved down the ramp in the kinetic friction section.

2) Should mass affect the static and kinetic friction coefficients? Explain.

3) Analyze sources of error (controllable and uncontrollable) in this lab.

(A good response is Urgently Required.)
 
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1) Find the forces on the puck. Are they constant? If not, what's changing?

2) Mass doesn't affect friction coefficients, the gravity and friction both operate on mass and therefore it cancels. Heavier mass gets pulled down more by gravity, but also gets slowed down more by friction.

3) You should know htis better than I. I don't know your setup but I would imagine you used some photo sensors for timing, you could mention something about air resistance.
 


1) The assumption that acceleration was constant as the object moved down the ramp in the kinetic friction section may not be entirely accurate. While it is true that the acceleration should be relatively constant due to the force of gravity acting on the object, there are other factors that could have affected this, such as air resistance or imperfections in the ramp surface. Additionally, as the object gains speed and moves further down the ramp, the force of kinetic friction may also increase, resulting in a slight decrease in acceleration. Therefore, while the assumption of constant acceleration may be a good approximation, it may not be entirely accurate.

2) Yes, mass can affect the static and kinetic friction coefficients. The coefficient of static friction is dependent on the normal force, which is affected by the mass of the object. A heavier object would have a greater normal force, resulting in a higher coefficient of static friction. Similarly, the coefficient of kinetic friction is also affected by the mass of the object. A heavier object would require more force to overcome the force of kinetic friction and maintain a constant velocity, resulting in a higher coefficient of kinetic friction. This relationship can be seen in the formula for friction force, where the coefficient of friction is multiplied by the normal force.

3) There are several sources of error that could have affected the results of this lab. Controllable errors could include human error, such as inaccuracies in measuring the displacement or time, or inconsistencies in applying the force to the puck. The angle of the ramp could also have been a source of error, as it may not have been perfectly consistent throughout the experiment. Uncontrollable errors could include external factors, such as air resistance or slight variations in the surface of the ramp, which could have affected the movement of the puck. Additionally, the puck itself may have had imperfections or inconsistencies that could have affected its movement. To minimize these errors, it is important to repeat the experiment multiple times and take an average of the results. Using more precise measuring tools and ensuring the ramp is properly set up can also help reduce errors.
 
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