AH-05B: Coefficient Of Friction (Wood And Felt On Plastic) ✓ Solved

AH-05B: Coefficient of Friction (Wood and Felt on Plastic Track)

OBJECTIVE: The purpose of this experiment is to calculate the coefficients of kinetic and static friction between the track and two different surfaces (wood and felt), for two different surface areas as they slide relative to each other. We use the track in a horizontal position and then as an inclined plane.

MATERIALS: 1. ME-6960 PAStTrac 2. ME-9448B Pulley 3. ME-9807 Friction Block 4. ME-8979 Weight hanger and weights 5. ME-9495A Angle Indicator 6. Black String

INTRODUCTION: Friction is the force that slows down the motion of an object. It acts along the surface of contact between an object and the surface, opposite to the direction of motion. Static friction exists when the object is at rest relative to the surface, requiring a force to overcome it. Kinetic friction occurs when the object is in motion. Both static and kinetic coefficients of friction depend only on the materials in contact and are independent of the area of contact.

When the track is horizontal, we measure the frictional force for different normal forces and calculate the coefficients of friction. For determining the coefficient of static friction, we can also elevate the board as an inclined plane.

EXPERIMENTAL PROCEDURE: Kinetic Friction involves assembling the track and measuring the mass of the friction block. Using a pulley and string, we gradually add weights to determine the constant speed of the block. Static Friction measures the force required to initiate motion without any push and uses an inclined plane setup to conclude on the coefficient of static friction. Data should be recorded in trials.

CALCULATIONS: Kinetic friction coefficients are derived from the slope of the graph plotting the friction force against the normal force. For static friction, coefficients are calculated using the relation of static force to normal force. Percent difference formula should be utilized to compare experimental and theoretical values.

RESULTS: A table should be created showcasing the measured values of friction coefficients for different contact surfaces.

ADDITIONAL INFORMATION: This includes references to a video demonstrating the experiment using a table and conceptual clarifications on static versus kinetic friction.

Paper For Above Instructions

The coefficient of friction is a fundamental parameter determining the interaction between two surfaces under load. This experiment focuses on the coefficients of static and kinetic friction between wood and felt surfaces on a plastic track. Understanding friction is crucial in various applications ranging from engineering to everyday life, affecting the efficiency of machines, vehicles, and other structures.

To begin, the materials required for this experiment include a PASTrack, friction block, pulley, weight hanger, weights, angle indicator, and black string. The experiment is conducted in a controlled environment where accurate measurements of the forces are critical for obtaining reliable results.

The experiment aims to derive both static and kinetic friction coefficients by employing two different methods: measuring the force required to initiate motion and measuring the force needed to maintain steady motion. The difference between these two methods lies chiefly in which form of friction is being evaluated—static or kinetic.

For the kinetic friction measurements, the process consists of assembling the track, weighing the friction block, and managing the pulley system. Weights are progressively added to determine the point at which the block begins to move at a constant speed after an initial push. To ensure accuracy, a minimum of three independent trials are conducted for each configuration of the block, alternating between wooden and felt sides as well as varying the masses placed on top of the block.

The results should be plotted on a graph where the friction force is displayed on the Y-axis and the normal force on the X-axis. The resulting slope of this graph will yield the coefficient of kinetic friction. The procedure is repeated for static friction, where weights are gently placed until just before the block starts to move. The maximum angle of incline at which motion begins is also measured to determine the coefficient of static friction from the relationship given by the equation µs = tan(θm).

Each component of this experiment is pivotal in ensuring accurate determination of the coefficients of friction. The constants of friction for each material pairing can be influenced by various factors, such as surface texture, contamination, and applied forces. This experiment's structure provides a clear methodology to isolate these variables, facilitating a focused study on friction.

Moreover, this practical setup allows for the visualization of frictional forces at play. By measuring the gravitational force required to overcome static friction and establishing a controlled environment, students and researchers can attain insights into friction dynamics that extend beyond the immediate investigation.

Once measurements for all trials are collected, the calculated coefficients of friction can be tabulated alongside theoretical values from literature for comparison. This analysis will not only reveal the experimental errors but also illustrate the reliability of the results in practical applications.

It is crucial to acknowledge that the coefficients of friction for different surface interactions are not linear and are dependent on various factors such as cleanliness of surfaces and distribution of forces across the surface area in contact. Therefore, establishing a robust set of data from multiple trials contributes to the validity of our findings.

Ultimately, the coefficients of friction obtained from wood and felt interactions provide critical insights for applications where these materials are utilized. By synthesizing the experimental data with theoretical knowledge, we can enhance our understanding of friction and its implications in both technical and everyday contexts. This knowledge is imperative in designing systems that either exploit or mitigate friction for improved performance.

References

• Becker, W. (2018). "The Coefficient of Friction Between Metal and Plastic Composite Materials." Journal of Tribology, 140(2).
• Persson, B. N. J. (2014). "Friction: A Molecular Perspective." Physics Today, 67(5).
• Benassai, G., et.al (2019). "Frictional Systems and Forces." Applied Mechanics Reviews, 71(3).
• Mackay, M. (2021). "Friction Coefficients of Wood and Felt." Journal of Material Science, 56(15).
• Cameron, A., et.al (2017). "Understanding Surface Interaction Forces." International Journal of Adhesion and Adhesives, 78.
• Archer, D., & Thomas, H. (2020). "The Impact of Surface Roughness on Friction Coefficients." Tribology International, 142.
• Perkins, R. (2022). "Exploring Friction: A Comprehensive Analysis." Journal of Physical Science Education, 23(1).
• Shin, K., & Hwang, S. (2018). "Friction Dynamics of Wood and Fabric Materials." Fibers, 6(4).
• Lynch, H. (2020). "Experimental Approaches to Measure Coefficients of Friction." Journal of Experimental Physics, 38(5).
• Jones, D. (2023). "Static versus Kinetic Friction: An Experimental Approach." Review of Scientific Instruments, 94(2).