The method and the results are on the friction and inclined planes lab. Do the analysis yourself first, then check the answers below.
Quick answer: Newton's second law states that the resultant force equals mass times acceleration, ΣF = ma. These answers go with the Physics 11-12 lab on friction and inclined planes: the graph, the calculations, the uncertainties and the conclusion explained, for all 8 analysis questions.
Here are the friction and inclined planes lab answers for physics grades 11-12: graph, calculations, uncertainties and conclusion. First do the lab yourself, then compare, and go back to the lesson if needed.
The sample data give μs = 0.51 for wood on wood and 0.89 for wood on sandpaper. Your values will depend on the materials, but the rougher surface should always give a steeper slipping angle and the mass should not matter.
Level: Physics grades 11-12 (A Level · IB · Class 11-12) · Curriculum: IB A.2
Both the friction limit and the weight component along the slope are proportional to the normal force, so the mass cancels and the angle stays the same.
Question 8 Improvement
Use a smaller increase in angle (a screw jack or a slow hand lift), measure the angle with a digital angle gauge, and average more trials.
