Halloun and Hestenes, 1985

This USA-based study attempts to identify and produce a taxonomy of university students' ‘common sense’ beliefs, which do not correspond with accepted scientific descriptions of forces and movement. 


  • It can be difficult to alter students’ belief systems even with demonstrations and examples. Repeated activities are required to present sufficient challenges to cause change.
  • Typical demonstrations used in classrooms alone are insufficient to drive needed change.

Learners’ ideas

  • Many students held the belief that the speed of a falling body is proportional to its weight.
  • Two-thirds of students held the belief that an object moves at a constant speed under a constant force. A smaller number (2%) held this belief consistently.
  • Many students believe that inanimate objects may serve as barriers to stop or redirect motion, but not as agents of a force.
  • Some students believe that gravity is a kind of impetus acquired by falling objects (like momentum) rather than a force acting on them.

Study Structure


  • To survey and analyse the ‘common sense’ beliefs of university students about motion and its causes.
  • Develop a taxonomy of ‘common-sense’ concepts which conflict with Newtonian theory as a guide to instruction.

Evidence collection

A mechanics-focused multiple-choice diagnostic test was employed to evaluate students' grasp of Aristotelian and Newtonian physics across various scenarios. Test question outcomes were analyzed using basic percentages to pinpoint prevalent misconceptions. From a smaller student subset, participants were extensively interviewed, supplemented by demonstrations to highlight contradictions in their intuitive notions. This data contributed to creating a taxonomy of how students conceptualize forces, aiding the design of activities to counter these misconceptions.

Details of the sample

The diagnostic test was applied to 478 university-age students. The follow-up interviews were conducted with 22 students.

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