It’s All Uphill Interative Background: With a partner read aloud “In this interactive, you will analyze the motion of a cart being pulled up an inclined plane at a constant speed. The angle of the incline can be modified by 10 o increments from 3090o. Three different masses can be selected. In each simulation, the cart is pulled to the same height – 1.0 m above the original starting point. For each simulation, the force applied is in the same direction as the displacement up the slope and reported on the screen. The displacement of the cart can be measured using the cm – ruler on the screen. Purpose: To determine the effect of the angle of an inclined plane upon the amount of force and and the amount of work done when pulling a cart upslope at constant sped and to the same height. Procedure: Go to “It’s All Uphill Interactive” in “the physics classroom” website (try googling it – it’s faster). Launch the interactive and enlarge it. Select a mass. Tap the Run Trial button. Record the angle and the force in the data table. Measure the displacement using the cm scale but convert to meters. The force and the displacement vectors are at 0 o. Choose a mass. Mass ________kg. Angle (o) Weight ________N. Force (N) 30.0 40.0 50.0 60.0 70.0 80.0 90.0 Choose a different mass. Displacement (m) Work (J) PE (J) Mass ________kg. Weight ________N. Angle (o) Force (N) Displacement (m) Work (J) 30.0 40.0 50.0 60.0 70.0 80.0 90.0 Analysis: Type the answers into your report with the tables and graphs. 1. Recall working with forces on an inclined plane. What force is causing the downhill pull? 2. What function do you expect the force magnitude to obey as the ramp angle increases? (We did this calculation previously use your notes). 3. Make a graph of force vs. angle (0 – 90o). Fit the graph with a curve. Make sure the graph axis start at 0,0. You may graph both masses on the same graph. 4. Now graph Work vs. Angle. Fit the graph with a line. Make sure the graph axis start at 0,0. You may graph both masses on the same graph. 5. Describe how increasing the angle affects the force (if at all). 6. Describe how increasing the angle affects the work (if at all). 7. Now graph work vs. PE. 8. What is the relationship between work and PE? 9. People use ramps to help them push carts uphill. They claim that using the ramp is less work than simply lifting the object straight up. Explain, using your graphs why they are wrong. What should they say?