SC.5.P.13.2 Investigate and describe that the greater the force applied to it, the greater the change in motion of a given object.

Transcription

1 SC.5.P.13.2 Investigate and describe that the greater the force applied to it, the greater the change in motion of a given object. Materials per group: 2 flexible rulers (plastic), 1 small ball of the same type (e.g., golf ball, tennis ball, ping pong ball, etc.), 2 metric tapes or 2 meter sticks, tape, Student Procedures (one per group) and Student Data sheet (one per student), safety goggles for each student Teacher Note: Pre-make a Student Data sheet for each group on chart paper as a visual framework for analyzing all charts during the explain portion of the exploration. In this activity students will gather data and analyze the results. Students will then make inferences based on the results of the exploration. Teachers should practice the exploration in order to have an understanding of where students may face challenges. Students are expected to follow student procedures with minimal help from the teacher. 1. Post the testable question: How does the amount of force applied to an object affect the distance it travels? 2. Distribute Student Procedures and Student Data sheet. 3. Give groups an opportunity to read the procedures before materials are distributed. Clarify procedures if students have questions before beginning the exploration or as they begin to work. 4. Distribute materials to groups. ALL students and adults in the classroom need to wear safety goggles in case a ruler breaks! 5. As students are working, circulate and observe their procedures for setting up the exploration and measuring distance. Teacher Note: Make note of differences among groups as the investigation proceeds. Check to see if groups are following procedures, but redirect students only if they are confused about the exploration. 6. Remind students to calculate the averages for their trials and record the averages in the last column in their data tables. 7. Have students post their charted data tables. Teacher Note: After students have completed the investigation, use the Probing Questions and Connecting Questions to connect the content to the activity during the Explain. Additional questions will need to be developed as you work with your class to help students think about the exploration, the data collected, and connections to science concepts.

2 Student Procedures 1. Tape the measuring tape to a flat, level surface. Be sure to tape the measuring tape to a flat, level surface at the 0 cm mark. 2. Lay the ruler next to the measuring tape. Make sure the ends of both measuring tools are lined up. 3. Place the ball at the start of the ruler. Place the flexible ruler behind the ball. 4. Bend the ruler back to the 1 cm line of the measuring tape, then release the ruler in order to exert a small amount of force on the ball. 5. Once the ruler is released, observe the motion of the ball. Record under 1 cm, Trial 1 the distance the ball travels on the group s data table and your Student Data sheet. 6. Repeat steps 3 5 two more times. Be sure to record your data under Trial 2 and Trial Place the ball at the start of the ruler. Place the flexible ruler behind the ball. 8. Bend the ruler back to the 2 cm line of the measuring tape, then release the ruler. 9. Once the ruler is released, observe the motion of the ball. Record under 2 cm, Trial 1 the distance the 10. Repeat steps 7 9 two more times. Be sure to record your data under Trial 2 and Trial Place the ball at the start of the ruler. Place the flexible ruler behind the ball. 12. Bend the ruler back to the 3 cm line of the measuring tape, then release the ruler. 13. Once the ruler is released, observe the motion of the ball. Record under 3 cm, Trial 1 the distance the 14. Repeat steps two more times. Be sure to record your data under Trial 2 and Trial Place the ball at the start of the ruler. Place the flexible ruler behind the ball. 16. Bend the ruler back to the 4 cm line of the measuring tape, then release the ruler. 17. Once the ruler is released, observe the motion of the ball. Record under 4 cm, Trial 1 the distance the 18. Repeat steps two more times. Be sure to record your data under Trial 2 and Trial Place the ball at the start of the ruler. Place the flexible ruler behind the ball. 20. Bend the ruler back to the 5 cm line of the measuring tape, then release the ruler. 21. Once the ruler is released, observe the motion of the ball. Record under 5 cm, Trial 1 the distance the 22. Repeat steps two more times. Be sure to record your data under Trial 2 and Trial 3.

3 Name: Student Data sheet How does the amount of force applied to an object affect the distance it travels? How far the ruler is bent back (cm) Trial #1 Trial #2 Trial #3 Average Distance Direction Traveled (straight, right, left) 1 cm 2 cm 3 cm 4 cm 5 cm *To find the average distance the marble traveled add the distance found in each trail, then divide by the number of trials. For example: 27cm + 26cm + 28cm = 81cm, then 81cm 3cm = 27cm. Independent variable (one thing you changed in your exploration): Dependent variable (what data you collected): Controlled variables (things we keep the same or constant): Other observations: How did the amount of force applied affect the distance the ball traveled? Use your data to support your answer.

4 Have students use data from the posted charts to explain as you ask the following questions. Be sure you give students adequate time to think about each question before they respond. Probing Questions Questions include, but are not limited to: 1. Look at the data on each group s chart. Do you see any patterns in the data? Describe the patterns you found. The pattern we want students to see is that the farther the ruler was bent back the greater the distance the ball traveled. 2. What relationship do you see between the amount the ruler was bent back and the distance the ball traveled? The relationship we want students to see is that the farther the ruler was bent back the more force it created, causing the ball to travel farther. 3. All of the data is not exactly alike. What might have caused this to happen? Possible answers include, but are not limited to: Students set up measuring tapes differently, groups did not start the ball at the same point on the ruler, students did not use same method for bending the ruler, students did not measure distance correctly, students did not use the same unit of measure, etc. 4. How could we make our investigation more accurate? Possible answers include, but are not limited to: Have the same person bend the ruler each time, have someone check over the work as it is done, make sure all of the measuring tapes are flat on the floor, etc. 5. What variables remained the same (constant) in this investigation? ball, set up, starting point, surface, measurement method, units of measurement, way the ruler is held when striking the ball, etc. 6. What is the independent variable? how far the ruler was bent back 7. What is the dependent variable? the distance the ball traveled 8. What did we measure in this investigation? how far the ruler was bent, the distance the ball traveled 9. What tool did we use to measure in this investigation? metric measuring tape

5 Questions to Connect the Exploration to Science Concepts Questions include, but are not limited to: 1. What statement can you make based on the data from this investigation? Possible answers include, but are not limited to: The greater the amount of force, the greater the distance the ball will roll. Students may also conclude that, with less force applied to the ball, the shorter the distance it will roll. 2. How can you use the data to support your statement? Possible answers include, but are not limited to: When the ruler was bent back to 1 cm, the ball rolled X cm. When the ruler was bent back 2 cm, the ball rolled Y cm. 2 cm is greater than 1 cm and Y is greater than X, so a farther the ruler is bent back the greater distance the ball will roll. When the ruler was bent back 3 cm, the ball rolled Z cm. 3 cm is greater than 2 cm and Z is greater than X and Y, so the farther the ruler is bent back the greater distance the ball will travel. 3. What do you think would have happened if each group started the ball at a different point? results would be different for each group 4. How would that have affected the data we collected? we would not be able to compare results because we did not carry out the investigation in the same way 5. What are multiple (or repeated) trials? when we use the same procedure and collect the data several different times 6. Why do you think multiple trials are important? In order to validate the results of an investigation. In this case, data from multiple groups following the same procedure and using the same materials will serve the function of multiple trials. 7. What is force? a force is a push or a pull that acts on an object 8. Was a push or a pull acting on the ball in our exploration? a push 11. What are some ways force may affect change in motion? Possible answers include, but are not limited to answers involving the greater the force applied to an object the greater the change in motion. Teacher Note: It is important for students to make the connection between forces and the motion of objects. In the investigation, the movement of the marble down the ramp was caused by the force of gravity pulling the marble down toward the surface of the Earth. Students should be able to give common examples of pushing and pulling forces, including gravity acting on objects. Friction is the force slowing and eventually stopping the movement of the marble which will be taught in an upcoming exploration.