Many pupils cannot correctly identify the forces acting on an object that has been set in motion but is slowing down.
Resources to Address This
Parachute games (11-14)
Source - SPT/ Mo02TA05
This resource outlines an activity where an object does not continue to fall faster and faster but reaches a final constant speed (or terminal speed), and the discussions you might have with your class.View Resource
Running out of driving force (11-14)
Source - SPT/ Mo03TL04
The driving force is only acting when there is contact - friction or drag are the forces affecting the motion once there is no driving force.View Resource
Episode 208: Preparation for drag forces (16-19)
Source - TAP/ Mechanics/ Drag forces
Consolidating understanding of forces acting on a falling object.View Resource
The following studies have documented this misconception:
- White, B. Y. () Sources of Difficulty in Understanding Newtonian Dynamics. Cognitive Science, 7 (1),
This study examined the responses of 40 high school science students (mean age 16.4) from an upper-middle class suburb of the Boston metropolitan area to a series of questions on Newtonian dynamics. Solutions and any comments made during the questions were recorded, as well as interviews and diagrams drawn.
- Clement, J. () Students' preconceptions in introductory mechanics. American Journal of Physics, 50 (1),
- Hewson, P. W. () Epistemological commitments in the learning of science: Examples from dynamics. The European Journal of Science Education, 7 (2),
This study took place at the University of the Witwatersrand, South Africa. It aimed to explore the role played by the epistemological commitments which a student holds in determining whether he or she accepts or rejects an argument.