Friction+Testing+Different+Surfaces

Your task is to investigate how factors, such as surface and weight, affect the size of frictional force.
 * Objective/Goal:**

Testing Frictional Force
 * Title:**

How does the amount of friction affects the roughness of the surfaces and the force that takes the pull? // *How does surface and weight affect the size of frictional force? //
 * Research Question/Problem:**

If the cork has the most friction, then it will take the most force because it has a rough surfaces. // If the surface causes more friction then, the movement will require more force because the friction is the resistance of force. // // **More friction, more force** //
 * Hypothesis (part 1):**

Newton meter Blocks
 * Material:**

1 2 3 Average Carpet || 4.0 Newton || 3.8 Newton || 4.5 Newton || 4.1 Newton || Cork || 10.0 Newton || 9.0 Newton || 9.8 Newton || 9.6 Newton || Plastic || 2.5 Newton || 2.8 Newton || 2.1 Newton || 2.5 Newton || 1 2 3 Average Carpet || 2.3 Newton || 2.0 Newton || 2.1 Newton || 2.13 N || Cork || 4.5 Newton || 4.9 Newton || 5.3 Newton || 4.9 Newton || Plastic || 1.0 Newton || 1.1 Newton || .9 Newton || 1 Newton ||
 * Data Table:**

If the mass increases then the force will also increase. Cork 1,000 grams || 10.0 Newton || 50 grams || 1.0 Newton || 0 || Newton || Cork 1,000 grams || 5.5 Newton || 500 grams || 2.3 Newton || 200 grams || 1.3 Newton ||
 * Hypothesis (part 2): **

Part 1: Cork, Carpet, Plastic (amount of friction) Part 2: Force
 * Independent Variables:**

Part 1: Weight, speed, shape, spring scale Part 2:
 * Controlled Variables:**

Part 1: Force Part 2: Mass
 * Dependent Variables:**

//Part I// 1. Draw a Data Table to record the different types of surfaces to be tested and the force needed to pull the block at a constant speed. Note that this data table should be included under the //__Data and Calculation section__//. 2. Place _______ grams in the box with the surface to be tested. 3. Attach your Newton meter to the block. 4. Using the Newton meter, try and pull the block along the surface. __Note the force needed to pull the block at a constant speed and record in your Data Table.__ 5. Repeat steps 2-4 for the other different surfaces.
 * Procedure:**

//Part II// 1. Draw a second Data Table to record the different weights to be tested and the force needed to pull the block at a constant speed. Note that this data table should be included under the //__Data and Calculation section__//. 2. Place _________ grams on the block with the surface to be tested. 3. Attach your Newton meter to the block. 4. Using the Newton meter, try and pull the block along the surface. __Note the force needed to pull the block at a constant speed and record in your second Data Table.__ 5. Repeat steps 2-4, placing different weights on the block. 6. Draw an x-y graph showing how the weight placed on the block affects the pulling force in Newton. Note that this graph should be included in the //__Results and Analysis section__//.

Answer the questions in complete sentences. 1. Explain what you have discovered about how different surface types affect the size of frictional forces. · We discovered that in pulling objects in rough surfaces is harder and you will have to exert more force than the others. · If the surface causes more friction then, the movement will require more force because the more friction, the more force you’ll need.
 * Results and Analysis:**

2. Use your results to explain, as an example, the best braking conditions for a car. · Dry surface and more friction.

3. Explain how changing the weight on the block affected the size of the frictional forces. · Because like of the block is heavier then we’ll need more force to pull it, if its lighter then, we won’t need that much force to pull it. · Changing the weight on the block increases the size of frictional force.

4. What variable did you need to control in this experiment so that it was a fair test? · For the first part the weight stayed the same. For the second part the surfaces stayed the same.

How does surface and weight affect the size of frictional force? If the surface causes more friction then, the movement will require more force because the friction is the resistance of force so **I therefore conclude that the more friction the surface has then the more force you’ll need because friction is always against the direction of motion.**
 * Conclusion:**