Practical 4 Measuring Acceleration
Introduction
In this experiment a motion sensor is used to record the velocity of a cart as it is pulled along a track by a mass hanging over a pulley. "Data studio" (the pasco interface software) is used to plot a velocity time graph, the acceleration is found from the gradient of that. The hanging mass is then varied. The aim of this experiment is to enhance students understanding of the relationship between graphs and motion and to introduce the idea of the relationship between Force and acceleration.
Assessment
This practical is not used as part of the assessment because too much information is given in the instructions, however it is marked according to the criteria so that students get some feedback
Feedback is given on the following criteria
DCP
Students should fill in a table including units and uncertainties. The table should have the same decimal points in a column, these should be reasonable. I also expect students to explain how they estimated the uncertainties. Students should plot a graph of a vs m. The graph should have error bars, labels and units. It should also have a best fit line and steepest and least steep lines.
CE
Students should comment on their graph and maybe use the gradient to find a known quantity, this should be compared with that quantity. The uncertainty in this value can also be found using the least steep and steepest lines. Weaknesses in the method should be commented on and ways to improve the method described.
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