1.A machine________________ the amount of work you do. A. DecreasesC. Increases B. Does not changeD. Divides Does not change

2. Jenni wants to lift 300 pounds of food onto a cruise ship. Answer the following questions for this scenario. A.Name two simple machines that will help Jenni load the food onto the ship. B. Explain why you picked each simple machine Be specific!! Pulley and Inclined Plane Pulley: used to change the direction of the food to the top of the ship Inclined Plane: will decrease the force used

3. Give two examples of each of the following simple machines. Wedge: Screw: Wheel and Axle: Inclined plane: Pulley: Lever: Axe, Door stopper Screw, Jar lid Car wheels, TrainsU-Haul ramp, skate park Ski Lift, Zip line Seesaw, Wheelbarrow

4. Jimmy uses a wheelbarrow to move potting soil to his garden. His wife Haley decides to just carry the bags of potting soil. Answer the following questions. A.Who did more work? Explain your reasoning! B. Explain which method you would use and why? Both did the same amount of work. Haley and Jimmy both just exerted a different amount of force and distance. I would use Jimmy’s method because the less force I exert the better. I would rather walk a further distance instead of exerting a large force.

5. Looking at he following inclined planes. Answer the following questions. Ramp 1 Ramp 2 A.Which ramp requires the car exert more of a force. Explain your reasoning. B.Which ramp would you cause your car to do more work? Explain your reasoning. Ramp 2, because for you to get up the steep hill it would require a greater force to avoid falling back down as well as wanting to have enough energy to get up the large hill. Both ramps require the same amount of work. In ramp 1 you would have to travel a further distance, but your force would be smaller. In ramp 2, you would exert a greater force for a smaller distance.

6. Answer the following questions applying your knowledge of simple machines. A.When you bite into a sandwich, your front teeth act as what simple machine? B.In an electric screwdriver, the handle is the wheel and the shaft is the______. C.A single fixed pulley such as a flag pole, change the ___________ of the input force. A. Amount C. Direction B. Type D. Screw Axle Wedge, because it is separating the sandwich. Direction

7. Perry is pushing a chair at a force of 3 N. Selena pushes desk at a force of 2N. Each person moves his or her object 5m. A.How much work does Perry perform? Show your work. B.How much work does Selena Perform? Show your work. 3N x 5m = 15 J 2N x 5m = 10 J

8. Name and explain three ways that you use simple machines in your life everyday.

9. Label the following a work(W) or not work (N) A.Throwing a football across a the field. B.Jumping rope outside. C.Sitting at a drive thru waiting for your Starbucks. D.Giving your favorite teacher a high five. E.Talking to your friends at lunch. F.Carrying your backpack. N W W W N N

10. Kim slams the door after fighting with her parents. She lams the door with a force of 25N and the door moves a distance of 3m. A.What is the work that Kim is doing on the door? Show your work. B.Draw a picture showing the direction of the force, and the direction of the door moving. Make sure to label your picture. Motion Force 25N X 3m = 75 J

11. A.Looking at the picture explain what the ramp will do to the man’s force and the distance? B. Is the man doing work why or why not? The ramp will decrease the force the man will exert and increase the distance he has to travel. Yes, the man is doing work because the box is moving in the same direction as his force. He pulls up and the box moves up.

12. A.Anna lift a crate into the back of her truck. She exerts a force of 200N a distance of 1.2m. Calculate the amount of work done on the crate and show your work. B. Anna then used an inclined plane to push the same crate into the truck. She exerts a force 77.5N a distance 3.1m What is the work done on the crate. 200N X 1.2 M = 240 J 77.5N X 3.1M = J

12. C. What does the inclined plane do for Anna’s work? Use the terms force and the distance to explain your answer. Anna’s work was the same, but she used less force to move the box over a greater distance.

13. Looking at he pulley diagram, answer the questions below. A.In pulley 2, which letter represents the input force? B.Which pulley has the greatest mechanical advantage and why? C. Pulleys change the ____________ of your force. Letter G Pulley 5 because there are more moveable pulleys and more rope, which means the force will be decreased and the distance is increase. The greatest mechanical advantage would be the system with the most number of pulley/rope ends. direction

14. A.Can a machine increase the force and the distance? Explain why or why not, by using a machine such as an inclined plane or pulley in your reasoning. B. When you use an inclined plane, what happens to the distance over which you exert a force? Machines cannot decrease the work. They can decrease force OR distance but not both. An example would include a pulley. You use less force to move the load, so force is decreased, but the distance will increase. Inclined planes increase the distance

15. Answer the following questions. A.How do you determine if work was done? Give three factors. B.Why does it take more work to move a 2.3kg bag of birdseed 100m than it takes to move a 1.6kg bag of cat food 50m? A force must be exerted, the object must move, the movement and the force must be in the same direction. The 2.3 kg bag will need more force and the distance is also greater. Increasing force and distance will lead to more work being done on the object.

16. Answer the following questions. A.A first class lever has the ___________ in the middle. B.Draw a picture and label the fulcrum, load, and the effort. C.Give an example of a first class lever. Fulcrum Teeter Totter

17. Answer the following questions. A.A second class lever has the __________ in the middle. B.Draw a picture and label the fulcrum, load and the effort. C.Give an example of a 2 nd class lever. Load Wheelbarrow

18. Answer the following questions. A.A third class lever has the __________ in the middle. B.Draw a picture and label the fulcrum, load and the effort. C.Give an example of a 3 rd class lever. Force Hammer

19. Draw a picture that shows a woman pushing a table. Draw a picture that shows a man pushing a chair. Each person moves his or her object 3 meters. In your picture include the force that each person exerted. Prove that the woman completed more work.

20. Answer the following questions. A.How can you exert a smaller force than is necessary to do a job if the amount of work stays the same. Give an example. B.If you move an object a shorter distance, what do you have to do to the force? Increase the distance by using an inclined plane or a pulley Increase the force. Instead of walking a box up a ramp, you could just lift the box into the truck.

21. Create a diagram that shows how you know if work is being done.

22.These weightlifters have used the same amount of force. They both started with their weights on the ground. Who has done the most work? Why? 1 2 Weightlifter 2 has done the most work because they have moved the weights a farther distance.

23. These weightlifters have used different amounts of weights. They both started with their weights on the ground. Who has done the most work? Why? 1 2 Weight lifter 1 has done more work because they have lifted more weight.

24. Jana lifted a 200-newton weight over her head to a distance of 2 meters above the ground. How much work did she do? 200N X 2m = 400J

25. Jacob picked up a 20-newton book from the floor. Then he passed it to Simone, who carried it for 20 meters. How much work did Simone do? Simone did not do any work because she carried the book. The force applied to the book and the direction the book moved do not agree.

26. Which pulley system would you use if you only wanted to change the direction of the force applied? Pulley system A

27. Which pulley system would you use if you only wanted to change amount of force needed to lift the load? Pulley system B

28. Which pulley system would reduce your force the most? What is the tradeoff for the reduction in needed force? Pulley system E. The trade off is pulling more rope.

29. Did any of these inclined planes cause the person to more work? Why or Why not? (Be specific) A.B. C. None of them caused the person to do more work. This is because as the force needed to move the object decreased then the distance the object had to move increased.

30. Which incline would you use to make the job the easiest? Why? A.B. C. Inclined plane C would be the easiest to do. It requires the least amount of force but you have to move the object over a longer distance to get the work done.