I have put the topics of motion under drag forces into the school environment. In the first part I have theoretically dealt with the quadratic law of resistance, which is deduced from the Bernoulli equation, and I have written a computer program for solving the differential equation governing the motion of a body in medium.
Based on the analysis of the experiments and theoretical starting points, I have compiled a procedure with which one can determine the conditions under which the drag force has to be taken into account and to what extent. In that way I have facilitate the teachers' s choice of a suitable body that can be used for demonstration experiments in the learning process. In the second part I have investigated the schoolchildren' s perceptions about the forces that act on the body at the moment when we push it, when it flies or freely falls. For this purpose, I have prepared test questions in which I have included typical experiments, such as the free fall and projectile motion. The experiments have been previously performed and analyzed, and then included in the test' s questions as a sequence of photographs. My aim has been to find out what are the misconceptions that schoolchildren have about drag forces and motion. I have examined and evaluated the answers I have gathered in various learning institutions. Finally I have analyzed and interpreted the results, and presented them using graphs and tables.
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