1. Motion and Design Lesson 4 Testing the Motion of Vehicles Carrying Load

2. Materials Timer per group Timer per group Record Sheet 4-A: Graphing Date copy per student Record Sheet 4-A: Graphing Date copy per student Standard vehicle per group Standard vehicle per group Bookend per group Bookend per group String with hooks per group String with hooks per group Colored pencils Colored pencils 16 small washers in a cup per group 16 small washers in a cup per group 2 blocks of wood per group 2 blocks of wood per group

3. Overview Adapt vehicle to carry a load of blocks and test how the weight of the load affects the vehicle’s motion. Adapt vehicle to carry a load of blocks and test how the weight of the load affects the vehicle’s motion. Will grasp the concept that the heavier the load, the slower the average speed of the vehicle. Will grasp the concept that the heavier the load, the slower the average speed of the vehicle. Will discuss and graph results and observations. Will discuss and graph results and observations. Develop an understanding of the relationships among force, mass, and change in motion. Develop an understanding of the relationships among force, mass, and change in motion.

4. Background Mass – amount of material in an object Mass – amount of material in an object Weight – amount of force gravity exerts on an object’s mass Weight – amount of force gravity exerts on an object’s mass On the Moon, people weigh 1/6 as much as on Earth, but their mass is the same. On the Moon, people weigh 1/6 as much as on Earth, but their mass is the same. Force affects motion of lighter and heavier vehicles. Force affects motion of lighter and heavier vehicles. The wood used in this unit is light enough that a vehicle carrying 2 blocks should move when pulled by 10 small washers. However, if a wooden block contains knots, it may be more dense, and thus heavier, than other blocks. The wood used in this unit is light enough that a vehicle carrying 2 blocks should move when pulled by 10 small washers. However, if a wooden block contains knots, it may be more dense, and thus heavier, than other blocks.

5. Using the Timer Round to the nearest whole number. Round to the nearest whole number. Start timer when object begins to move. Start timer when object begins to move. Stop timer when weight hits the floor. Stop timer when weight hits the floor. Demonstrate and practice using the timer. Demonstrate and practice using the timer. Time the motion of a student moving across the classroom. Time the motion of a student moving across the classroom. What are some examples of motion that we measure with time? (foot race, swimming meets, horse race, car trip) What are some examples of motion that we measure with time? (foot race, swimming meets, horse race, car trip)

6. How would adding blocks to your vehicle change the way the vehicle moves? How would adding blocks to your vehicle change the way the vehicle moves? Write predictions in notebook. Write predictions in notebook. Hold up 2 blocks and vehicle. How could you adapt your vehicle to hold 2 blocks of wood while moving? Hold up 2 blocks and vehicle. How could you adapt your vehicle to hold 2 blocks of wood while moving?

7. To make this investigation fair, each group will attach the blocks in the same manner.

8. Testing the motion of Vehicles Carrying a Load Set up the Falling-weight system as you did in Lesson 3. Set up the Falling-weight system as you did in Lesson 3. Add 2 blocks to your vehicle. Squeeze the crossbars to make certain the blocks are held in place. Add 2 blocks to your vehicle. Squeeze the crossbars to make certain the blocks are held in place.

9. Make certain that 1 end of the string is attached to the vehicle and the other end is threaded through the opening in the bookend. Make certain that 1 end of the string is attached to the vehicle and the other end is threaded through the opening in the bookend. Pull the vehicle back until the hook is at the top edge of your work space. Pull the vehicle back until the hook is at the top edge of your work space. One partner hold vehicle in place. One partner hold vehicle in place. Place 10 small washers on the hook. Place 10 small washers on the hook. Hang the weights over the edge of your work space. Make sure the hook is not stuck on the table edge. Hang the weights over the edge of your work space. Make sure the hook is not stuck on the table edge.

10. Let go of the vehicle. If it does not move, tap it slightly. Let go of the vehicle. If it does not move, tap it slightly. Can the 10 washers move the vehicle? Can the 10 washers move the vehicle? If the vehicle still does not move, add more small washers, one at a time. If the vehicle still does not move, add more small washers, one at a time. Stop adding washers when the vehicle begins to move, even slightly, across the table. Stop adding washers when the vehicle begins to move, even slightly, across the table.

11. Count your washers and write the number on Record Sheet 4-A. Use this number of washers throughout this investigation. Do not change the number of washers. Count your washers and write the number on Record Sheet 4-A. Use this number of washers throughout this investigation. Do not change the number of washers. Get your timer. Get your timer. Pull the vehicle back again until the hook is at the top edge of the table. Pull the vehicle back again until the hook is at the top edge of the table. When you are ready to begin set the timer to 0. When you are ready to begin set the timer to 0. As you let go of the vehicle, start the timer. (If the paper clip gets stuck on the edge of the table, start over.) As you let go of the vehicle, start the timer. (If the paper clip gets stuck on the edge of the table, start over.) Stop the timer when the falling weights touches the floor. Stop the timer when the falling weights touches the floor.

13. Talk with your group about your vehicle’s motion. Talk with your group about your vehicle’s motion. How did the blocks affect how the weighted string pulled your vehicle? How did the blocks affect how the weighted string pulled your vehicle?

14. Will use a timer to measure how long it takes your vehicle to move. Will use a timer to measure how long it takes your vehicle to move. Keep the number of washers the same for each trial. Change only the load carried by the vehicle. Keep the number of washers the same for each trial. Change only the load carried by the vehicle. Color a circle above the number on the line plot that represents the number of seconds it took your vehicle to travel a distance equal to the height of your work space while carrying a load of wooden blocks. Color a circle above the number on the line plot that represents the number of seconds it took your vehicle to travel a distance equal to the height of your work space while carrying a load of wooden blocks.

17. Vehicle + 2 Block (green dots) Put 2 blocks between the crossbars. Put 2 blocks between the crossbars. Squeeze the crossbars so the block stays in place. Squeeze the crossbars so the block stays in place. Pull the vehicle back until the hook is at the top edge of the table. Pull the vehicle back until the hook is at the top edge of the table. Reset your timer to 0. Reset your timer to 0. Let go of the vehicle. Let go of the vehicle. Stop the timer when the weights hit the floor. Stop the timer when the weights hit the floor. Color your results on the graph green. Color your results on the graph green. If you get the same time as an earlier trial, color a circle directly above the circle from the other trial. If you get the same time as an earlier trial, color a circle directly above the circle from the other trial. Do this 5 times altogether. Do this 5 times altogether.

18. Vehicle + 1 Block (blue dots) Only use 1 block between the crossbars. Only use 1 block between the crossbars. Squeeze the crossbars so the block stays in place. Squeeze the crossbars so the block stays in place. Pull the vehicle back until the hook is at the top edge of the table. Pull the vehicle back until the hook is at the top edge of the table. Reset your timer to 0. Reset your timer to 0. Let go of the vehicle. Let go of the vehicle. Stop the timer when the weights hit the floor. Stop the timer when the weights hit the floor. Color your results on the graph blue. Color your results on the graph blue. If you get the same time as an earlier trial, color a circle directly above the circle from the other trial. If you get the same time as an earlier trial, color a circle directly above the circle from the other trial. Do this 5 times altogether. Do this 5 times altogether.

19. Vehicle (red dots) Remove all the blocks. Remove all the blocks. Pull the vehicle back until the hook is at the top edge of the table. Pull the vehicle back until the hook is at the top edge of the table. Reset your timer to 0. Reset your timer to 0. Let go of the vehicle. Let go of the vehicle. Stop the timer when the weights hit the floor. Stop the timer when the weights hit the floor. Color your results on the graph red. Color your results on the graph red. If you get the same time as an earlier trial, color a circle directly above the circle from the other trial. If you get the same time as an earlier trial, color a circle directly above the circle from the other trial. Do this 5 times altogether. Do this 5 times altogether.

20. Discussion What did you observe when testing various loads or blocks? What did you observe when testing various loads or blocks? How did the vehicle move when it was loaded with 2 blocks? How did the vehicle move when it was loaded with 2 blocks? How did the motion of the vehicle change when you removed 1 block? How did it change when you removed both blocks? How did the motion of the vehicle change when you removed 1 block? How did it change when you removed both blocks? What did you think would happen if you added a 3 rd or 4 th block to the vehicle? What did you think would happen if you added a 3 rd or 4 th block to the vehicle?

21. Discussion When the vehicle carried no blocks, what was left to influence its motion or the weight of the vehicle? When the vehicle carried no blocks, what was left to influence its motion or the weight of the vehicle? What can you conclude about the effects of load (such as blocks) on a vehicle’s motion? (The heavier the vehicle, the longer the vehicle takes to respond to a force.) What can you conclude about the effects of load (such as blocks) on a vehicle’s motion? (The heavier the vehicle, the longer the vehicle takes to respond to a force.) What situations at home or in school may be similar to what you tested in this lesson? What situations at home or in school may be similar to what you tested in this lesson?

22. After Investigation Describe approximately how much time it took your vehicle in each trial to move the given distance. Describe approximately how much time it took your vehicle in each trial to move the given distance. By taking repeated measurements and selecting a value from these measurements, you can get a more representative measure of the time it took your vehicle to move than if you measure only once. By taking repeated measurements and selecting a value from these measurements, you can get a more representative measure of the time it took your vehicle to move than if you measure only once.

23. Extensions Investigate how the position of the vehicle’s load might affect your results. Try stacking blocks horizontally instead of vertically or a front loading vehicle instead of a back loading one. Investigate how the position of the vehicle’s load might affect your results. Try stacking blocks horizontally instead of vertically or a front loading vehicle instead of a back loading one. Imagine you are transporting an important shipment across the continent. What will the shipment be? What is the destination? Why must the shipment be delivered? How will you transport it? After you have delivered the load, how will the return trip be different? Imagine you are transporting an important shipment across the continent. What will the shipment be? What is the destination? Why must the shipment be delivered? How will you transport it? After you have delivered the load, how will the return trip be different?

24. Extensions Continued Use timer to measure the elapsed time of various events, such as the length of their lunch period, the amount of time it takes someone to run across the playground, the time it takes for a car to travel between 2 telephone poles, or how fast a fish swims the length of the fish tank. Use timer to measure the elapsed time of various events, such as the length of their lunch period, the amount of time it takes someone to run across the playground, the time it takes for a car to travel between 2 telephone poles, or how fast a fish swims the length of the fish tank. Research and write about various load-bearing vehicles. Including how they are different from each other. Research and write about various load-bearing vehicles. Including how they are different from each other. Display photographs of various load-bearing vehicles. Using materials from home, such as shoe boxes and empty spools to create a model of one of the displayed vehicles. Display photographs of various load-bearing vehicles. Using materials from home, such as shoe boxes and empty spools to create a model of one of the displayed vehicles.

25. The End!!!