1. 1.Use the following information to determine the force required to lift the load using a 1 st class lever. 2.What would DF have to be to make the applied force half of what it was for #1 above? 3.What is the mechanical advantage of a movable pulley system? How much F to lift L = 100 lbs? F = ? L = 100 lbs. DF = 40 ft. DL = 40 ft. F = ???? February 2, 2010 DRILL

2. 1.Sketch a picture 2.Write your equation 3.Substitute values 4.Solve for unknown FORCE/DISTANCE MULTIPLIERS 100 lbs. 40 ft. F = ? L x DL = F x DF 100 lbs x 40 ft = F x 40 ft 4000 ft-lbs = F x 40 ft 40 ft 40 ft F = 100 lbs. What can you say about the relationship between the Force, Load, DF, and DL by this problem? U3d-L13

3. 2.What would DF have to be to make the applied force half of what it was for #1 above? FORCE/DISTANCE MULTIPLIERS 100 lbs. 40 ft.DF = ? F = 50 lbs. L x DL = F x DF 100 lbs x 40 ft = 50 lbs x DF 4000 ft-lbs = 50 lbs. x DF 50 lbs 50 lbs DF = 80 ft. What can you say about the relationship between the Force, Load, DF, and DL by this problem? U3d-L13

4. 3.Movable Pulley – splits the work in half. How many strands are supporting the load? What is the MA of a movable pulley? How many lbs of force are required to lift 100 lbs of load? When a movable pulley is used, the force needed to lift a load is half that of the load. 2 50 2 PULLEY

5. Simple Machines can be: –Force Multiplier: Increases the force applied to the work at hand –Distance Multiplier: Increases the distance the load moves FORCE/DISTANCE MULTIPLIERS MECHANICAL ADVANTAGE MA is the number of times a mechanical device multiplies the Applied Force U3d-L12

6. Final Design Report and Project due Thursday Requirements: 1.All steps to include required information as well as rubric guidelines. Test/Quiz Wednesday on the steps of the Engineering Design Process – know the order of the steps and what is required for each step U3d-L12

7. USE THE RUBRIC! USE STEP GUIDELINES YOU SHOULD NOW HAVE IN YOUR NOTES U3d-L12

8. 1.Describe the situation that needs a technological solution a.What must your solution accomplish? b.What is the need or desire? Step 1 – Defining the Problem Outcome: Sentences, Paragraphs, Lists U3d-L12

9. 2.Establish the criteria and constraints under which the solution must operate a.What are solution requirements (criteria)? b.What are the limitations on the solution (constraints)? Step 2 – Identifying Criteria/Constraints Outcome: Sentences, Lists, Charts U3d-L12

10. Gather information – obtain background information needed to begin developing solutions to the problem/situation a.What specific information do you need to know prior to designing your solution? b.What criteria/constraint details must you be informed about? Steps 3 & 4 – Brainstorm/ Research/ Generate Ideas Outcome: Sentences, Paragraphs, Lists, Charts U3d-L12

11. 5.Develop possible solutions to the problem/opportunity a.Come up with at least 3 solutions to the problems you must solve b.General sketches, then detailed sketches c.Does each satisfy the criteria and fit within the constraints? Outcome: Sentences, Lists, Charts, Sketches Step 5 – Exploring Possibilities U3d-L12

12. 6.Isolate, refine, and detail the best solution a.Modify b.Integrate components c.Improve d.Detailed sketches Outcome: Sentences, Lists, Charts, Sketches Step 6 – Select an Approach U3d-L12

13. 7.An explanation of your final design a.Detailed drafted drawings b.Steps to make it c.Explanation of how it satisfies all criteria and constraints Outcome: Sentences, Lists, Charts, Sketches Step 7 – Develop Design Proposal U3d-L12

14. 8.Make it! Prototype will be tested Outcome: Sentences, Lists, Charts, Sketches, Prototype Step 8 – Make Model/Prototype U3d-L12

15. 9.Once you make your prototype, test it to ensure that it works. Also, calibrate your prototype to toss ball desired distances. DOCUMENT YOUR TESTING PROCESS and RESULTS You should be testing by this Thursday’s class. Step 9 – Test Model/Prototype U3d-L12

16. 10.After testing in step 9, document any changes you need to make. Step 10 – Refine the Design 11.Implement any changes decided upon in step 10. Prepare for the competition. Step 11 – Create/Make it U3d-L12

17. 12.Describe how the final solution meets design criteria and constraints. FINAL COMMUNICATION REPORT (including all steps) due Monday 2/16 Step 12 – Communicate Processes and Results U3d-L12

18. Class Competition U3d-L12