, what effect on Flim was produced by a) changing the nature of the surfaces, b) changing the normal force, and c) changing the area of contact between the surfaces? Be sure to cite specific results that support your responses to parts a-c.
To determine the effects on friction (Flim) produced by changing the nature of the surfaces, changing the normal force, and changing the area of contact between the surfaces, you can conduct experiments and analyze the results. Here's how you can investigate each factor individually:
a) Changing the nature of the surfaces:
1. Set up an inclined plane or any other inclined surface.
2. Place an object with known weight and dimensions (for consistent contact area) on top of the surface.
3. Measure the weight of the object and record it.
4. Gradually change the nature of the surfaces by replacing the material of the inclined surface, for example, from rough sandpaper to smooth glass.
5. Gradually increase the angle of the inclined surface until the object starts to slide.
6. Record the angle at which the object starts sliding for each surface.
Results:
You will observe that different surfaces will have different angles at which the object starts sliding. Surfaces with higher coefficients of friction will require a steeper angle for the object to slide, indicating a higher friction force. Surfaces with lower coefficients of friction will allow the object to start sliding at lower angles, suggesting a lower friction force.
b) Changing the normal force:
1. Set up a flat surface or an inclined plane.
2. Place an object of known weight and dimensions on top of the surface.
3. Measure the weight of the object and record it.
4. Gradually increase or decrease the normal force acting on the surface by adding or removing weights on top of the object.
5. Gradually increase the angle of the inclined surface until the object starts to slide.
6. Record the angle at which the object starts sliding for each normal force level.
Results:
You will notice that increasing the normal force will generally increase the friction force, making it more difficult for the object to start sliding. Consequently, the angle required for the object to slide will be larger. Conversely, decreasing the normal force will reduce the friction force, resulting in a lower angle needed for the object to start sliding.
c) Changing the area of contact between the surfaces:
1. Set up an inclined plane or any other inclined surface.
2. Place an object with a fixed weight on top of the surface.
3. Measure the weight of the object and record it.
4. Gradually change the contact area between the object and the surface. For example, modify the shape or size of the object's base.
5. Gradually increase the angle of the inclined surface until the object starts to slide.
6. Record the angle at which the object starts sliding for each contact area.
Results:
When you change the area of contact between the surfaces, you will discover that larger contact areas generally result in higher friction forces. Consequently, it will require a steeper angle for the object to slide. Conversely, reducing the contact area will decrease the friction force, allowing the object to start sliding at a smaller angle.
By conducting experiments like the ones described above, you can obtain empirical data and specific results that support your responses to various parts (a-c) of the question.