AB5_Lab09_AmandaHeikes - 1 What is represented by the arrows labeled N D and F N= Surface Perpendicular Component D= Surface Parallel Component F=

1) What is represented by the arrows labeled N, D, and F? N= Surface Perpendicular Component D= Surface Parallel Component F= Friction 2) Start with dry soil (friction coefficient = 0.5u), a rock with mass of 100g at an angle = 0. What is the value of N, D, and F? (You may need to toggle the angle from zero to some value and then back to zero to re-set the module.) F= 50 D= 0 N= 100 3) What are the values of N, D, and F when the angle is 26º? And 27º, and 45º? 26º F= 44.95 D= 43.85 N= 89.9 27º F= 44.6 D= 45.4 N= 89.15 45º F= 35.4 D= 70.75 N= 70.75 4) Describe how D changes as the slope angle increases. At what angle does the rock begin to slide? This is defined as the Failure angle. D gets larger as the angle gets larger. The rock begins to slide at 26.7 º. 5) Complete the following table for 100g of each rock type listed. Create an X-Y scatter plot (without lines connecting data points) of Failure Angle vs. Friction Coefficient. Produce a trend line including the formula to fit the data – use the ‘Chart’ menu and select ‘add trend line’ choice. Write the equation and discuss how failure angle changes as a function of frictional coefficient (look at the equation and the graph)?