F=ma Lesson Plan Standard: Analyze data to support the claim that Newton’s second law of motion describes the mathematical relationship among the net force on a macroscopic object, its mass, and its acceleration. Clarification Statement: Examples of data could include tables or graphs of position or velocity as a function of time for objects subject to a net unbalanced force, such as a falling object, an object rolling down a ramp, or a moving object being pulled by a constant force. Assessment Boundary: Assessment is limited to one­dimensional motion and to macroscopic objects moving at non­relativistic speeds. Science and Engineering Practices: Analyzing and interpreting data Analyzing data in 9–12 builds on K–8 and progresses to introducing more detailed statistical analysis, the comparison of data sets for consistency, and the use of models to generate and analyze data. ● Analyze data using tools, technologies, and/or models (e.g., computational, mathematical) in order to make valid and reliable scientific claims or determine an optimal design solution. Crosscutting Concept:: Cause and Effect • Empirical evidence is required to differentiate between cause and correlation and make claims about specific causes and effects. There are two methods to this lesson. One is student driven, the teacher just sits back and watches. The other is teacher led. Choose which ever way you are more comfortable with. Student Objective: Compare the acceleration of objects with different forces applied to them(I.V. 1) and compare the acceleration of different masses(I.V. 2) with the same force applied. With this data students should be able to determine the relationship between Force and Acceleration(directly proportional) and Mass and Acceleration(inversely proportional). Procedure A: ● ● ● ● Short Teacher led Q&A leading the students to defining Force as a push and a pull. Plan Day; Ask students to devise a device that will test the relationship between Force, Mass, and Acceleration. ○ Students in this case came up with the idea of rolling/throwing different size balls(not the best because of the added variable of size­ discussed the problem with students), rolling carts of different masses(did this, but requires some extra equipment, and there are some problems with the results), and throwing the same size object with different masses(this idea evolved into the catapults pictured above). ○ There are many other examples they could do, they just have to a) bring their own supplies for their test and b) explain in detail how their design is going to test the required variables. Y ou need to approve the designs before the build day. Build Day; Give students a class period to begin building their apparatus. Allow them to make mistakes and redesign in the process. ○ If they finish the build with enough time allow them to begin their data collection Data Collection; There is the possibility for either quantitative or qualitative data in this lab depending on the direction the students take with their design. The graphs below were created based off qualitative data. ● Analysis and Discussion; Discuss with students the mathematical representations of these graphs in formula form( F=a, 1/m=a). Help them combine this into the equation F=ma ○ Have them do the file F, m, a math and have them explore the terms directly and indirectly proportional. ○ Have them practice word problems using the equation they derived. ○ Show them the technical wording of Newton’s Second Law of Motion and have them break it down according to their findings. Procedure B: Along these same lines only give them exact instructions of what device you would like them to use for the investigation. Also, you may want to explain Newton’s Second Law first if you don’t feel they will be able to reach the correct conclusions by the end of the investigations. Have them use their data to support the statement instead of deriving the statement themselves.