Abstract:

In Newtonian physics, free fall is any motion of a body where its weight is the only force acting upon it, most of the students even when they have a good understanding about free fall, they are not able to understand what happened with an object velocity when its falls under the influence of other forces like the air resistance. When an object which is falling under the influence of gravity or subject to some other constant driving force is subject to a resistance or drag force which increases with velocity, it will ultimately reach a maximum velocity where the drag force equals the driving force. This final constant velocity of motion is called a terminal velocity. When we discuss in classroom about this matter students in an introductory college physics course very often have difficulties in learning this concept, that’s why we designed a didactic sequence with the objective to guide the students to understand, identify and change their misconceptions. This didactic sequence includes a 20 questions multiple choice test and assessment tool to determinate the level of conceptualization of students. The questions were initially selected to assess student’s qualitative conceptions about the causes of terminal velocity. In this paper we discuss the instrument design application and implementation of the didactic sequence in a group of 17 engineering freshmen. The didactic sequence used as the core the fall of a parachutist who tries to break the record in free fall based on a journalistic note, bringing the student to a real-life problem. Didactic sequence also promotes active learning through collaborative student learning and promotes metacognition skills.

Keywords:

Terminal velocity, didactic sequence, assessment learning.