Reference no: EM133084161
Experiment 1: Static Friction
Question 1: What is the mass of the wooden block plus the brick? Include appropriate units.
Question 2: What is the normal force N exerted on the block when it is resting on a horizontal surface with the brick on top? Include appropriate units.
Question 3: What is the coefficient of static friction? Express your answer as the mean plus or minus the standard deviation of the 10 trials. Use the principles in the Precision and Error document to guide your use of significant figures in your answer.
EXPERIMENT 2: Varying the mass
Question 4: What is the mass of the second brick? Include appropriate units.
Question 5: What is the total normal force N exerted on the block when both bricks are on top? Include appropriate units.
Question 6: What is the coefficient of static friction you measured in this experiment? Express your answer as the mean plus or minus the standard deviation of the 10 trials.
Question 7: Is the coefficient of friction you measured in Experiment 2 consistent with the coefficient of friction you measured in Experiment 1? Use the larger of the two standard deviations to determine whether or not it is consistent. If it is not consistent, explain why you think they might be different.
EXPERIMENT 3: Varying the surface area
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Maximum force(F)
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Coefficient of static friction(µ=F/N)
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Time(s)
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10.978
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0.428868331
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2.44
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10.834
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0.423242804
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2.42
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12.254
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0.478716755
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5.4
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10.526
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0.411210426
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2.9
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10.567
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0.412812139
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2.76
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10.299
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0.402342407
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2.66
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10.201
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0.398513923
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2.48
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10.465
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0.40882739
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3.12
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9.964
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0.389255243
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2.34
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10.228
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0.39956871
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2.14
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MEAN=0.415335813
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standard deviation=0.02518629
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Question 8: What is the coefficient of static friction you measured in this experiment? Express your answer as the mean plus or minus the standard deviation of the 10 trials.
Question 9: Is the coefficient of friction you measured in Experiment 3 consistent with the coefficient of friction you measured in Experiment 1? Again, use the larger of the two standard deviations to determine this.
Question 10: What might explain any discrepancy in the coefficient of friction measured in Experiment 3 vs Experiment 1? It may help to look carefully at the angle of the string in the two cases and think about the limits of the force sensor that were discussed in the previous lab.
EXPERIMENT 4: KINETIC FRICTION
Question 11: Based on the statistics, what was the average force required to maintain a constant velocity?
Question 12: What is the coefficient of kinetic friction?
Question 13: How does it compare to the coefficient of static friction?
Question 14: What do you think is the largest source of error in these experiments?
Question 15: How could the experiment be improved to reduce the error?