Problem Set #1 Constant Velocity Motion A diagram representing the motion of two cars is shown below. The number near each dot indicates the clock reading in seconds when the car passes that location. (a) Indicate times when the cars have the same speed. (b) Indicate times when they have the same position. Explain your reasoning. Car 1 0 2 3 4 U Car 2 Ability A4: Is able to use representations to solve problems Adequate Needs Work Inadequate Missing The problem is solved The problem is solved The problem is solved No attempt is made to solve correctly with at least three correctly but there are only correctly but no the problem. different representations two representations: math and representations other than (sketch, physics words explaining the math were used. representation and math or solution. sketch, words and math, or some other combination) Ability F3: Is able to clearly explain their reasoning in words Adequate Needs Work Inadequate Missing Explanation is clear, Explanation is slightly Explanation is incoherent, No verbal explanation is detailed, and shows physical unclear, missing some minor incomplete, confusing, or provided and conceptual information, covers what was inconsistent with the work understanding. Explains done but is missing why it shown. both what was done and was done. why.10:42 AM Tue Sep 13 . . . * 01 @ 71% Done Problem+Set+01 (1 of 128) Q . .. The positions of objects A and B with respect to Earth depend on time as follows: x (t) = 10.0m - (4. 0m/s)t and x (t) =- 12m + (6m/s)t. Represent their motions using position-time graphs. Use two different methods to find where the two objects will meet. Ability A2: Can construct new representations from previous representations Adequate Needs Work Inadequate Missing Representations are Representations are created Representations are No attempt is made to constructed with all given without mistakes, but there is attempted but use incorrect construct a different (or understood) information information missing, i.e. nformation or the representation and contain no major flaws. labels, variables. representation does not agree with the information used. Ability A4: Is able to use representations to solve problems Adequate Needs Work Inadequate Missing The problem is solved The problem is solved The problem is solved No attempt is made to solve correctly with at least three correctly but there are only correctly but no the problem. different representations two representations: math and representations other than (sketch, physics words explaining the solution. math were used. representation and math or sketch, words and math, or some other combination) Ability D5: Is able to evaluate the results by means of an independent method Adequate Needs Work Inadequate Missing A second independent A second independent A second independent No attempt is made to method is used to evaluate method is used to evaluate method is used to evaluate evaluate the consistency of the results and the the results. The results of the the results. However, there is the result using an evaluation is correctly done two methods are compared little or no discussion independent method. with the experimental correctly using experimental the differences in the results uncertainties. The uncertainties. But there is due to the two methods discrepancy between the little or no discussion of the results of the two methods, possible reasons for the and possible reasons are differences when the results discussed. are different.For each of the position-time graphs below, draw the corresponding velocity-time graph. Explain how you know the velocity-time graph you drew is consistent with the graph given. (a) 0 t2 to ItA ts! (b) 0 12 t3 Ability A2: Can construct new representations from previous representations Adequate Needs Work Inadequate Missing Representations are Representations are created Representations are attempted No attempt is made to constructed with all given without mistakes, but there is but use incorrect information or construct a different (or understood) information information missing, i.e., the representation does not representation and contain no major flaws labels, variables. agree with the information used. Ability F3: Is able to clearly explain their reasoning in words Adequate Needs Work Inadequate Missing Explanation is clear, detailed, Explanation is slightly Explanation is incoherent, No verbal explanation is and shows physical and unclear, missing some minor incomplete, confusing, or provided. conceptual understanding. information, covers what was inconsistent with the work Explains both what was done done but is missing why it shown and why. was done.. . . ... You are an observer on the ground. (a) Draw two motion diagrams representing the motions of two runners moving at the same constant speeds in opposite directions toward you. Runner 1, coming from the east, reaches you in 5 s, and runner 2 reaches you in 3 s. (b) draw a motion diagram for runner 2 as seen by runner 1. Explain your work. Ability Al: Can extract the information from representation correctly Adequate Needs Work Inadequate Missing All necessary information has Some of the information is Information that is extracted No visible attempt is made been extracted correctly and extracted correctly, but not all contains errors such as to extract information from written in a comprehensible of the information. For labeling quantities incorrectly, the problem text. way. Objects, systems, physical example, physical quantities mixing up initial and final quantities, initial and final are represented with numbers states, choosing a wrong states, etc. are identified there are no units. Or system, etc. Physical correctly and units are correct. directions are missing quantities have no subscripts Physical quantities have Subscripts for physical (when those are needed). consistent subscripts. quantities are either missing or inconsistent. Ability A6: Is able to construct a motion diagram Adequate Needs Work Inadequate Missing The diagram contains no Diagram has the correct Diagram does not show proper No representation is errors and it clearly spacing of the dots but is motion: either lengths of constructed. describes the motion of the missing velocity arrows or arrows (both velocity and object. Dots, velocity arrows velocity change arrows. velocity change) are incorrect and velocity change arrows or missing and or spacing of are correct. are incorre Ability F3: Is able to clearly explain their reasoning in words Adequate Needs Work Inadequate Missing Explanation is clear, detailed, Explanation is slightly Explanation is incoherent, No verbal explanation is and shows physical and unclear, missing some minor incomplete, confusing, or provided. conceptual understanding. information, covers what was inconsistent with the work Explains both what was done done but is missing why it was shown and why. done