Many pupils think that a force is needed to keep an object moving with a constant speed

Forces and Motion


Pupils may instead think that a constant speed results from a constant force – and the bigger the force on an object, the faster it moves.

Resources to Address This

  • Measuring constant speeds (11-14)

    Source - SPT/ Mo02TA03

    This resource helps student to gain experience of timing objects moving at a constant speed and to recognise that the forces acting add to zero.

    View Resource
  • Constant (14-16)

    Source - SPT/ Mf02TL04

    How to use this word in the motion topic.

    View Resource
  • Episode 209: Drag air resistance terminal velocity (16-19)

    Source - TAP/ Mechanics/ Drag forces

    Exploring the part played by gravity and drag when objects fall with constant velocity.

    View Resource


The following studies have documented this misconception:

  • Clement, J. () Students' preconceptions in introductory mechanics American Journal of Physics 50 1


    Review sheet

  • Trumper, R. and Gorsky, P. () A cross-college age study about physics students' conceptions of force in pre-service training for high school teachers Physics Education 31 4


    Review sheet

  • Watts, D. M. () A study of schoolchildren's alternative frameworks of the concept of force International Journal of Science Education 5 2 217-230

    This study used an interview approach to identify the conceptions of force of 12 students aged 11-17. Students were drawn from a range of schools in the Greater London area, from both junior science classes and advanced-level physics classes.
    Review sheet

  • Ogborn, J. () Understanding students' understandings: An example from dynamics International Journal of Science Education 7 2


    Review sheet

  • Saltiel, E. and Malgrange, J. L. () 'Spontaneous' ways of reasoning in elementary kinematics European Journal of Physics 1 2


    Review sheet

  • Lythott, J. () "Aristotelian" was given as the answer, but what was the question? In H. Helm and J. D. Novak (Eds.), Proceedings of the International Seminar: Misonceptions in Science and Mathematics Cornell University Ithaca, NY


    The self-proclaimed purpose of this paper is "to raise questions concerning the advisability of the continued use of such adjectives, specifically "Aristotelian", without a concerted effort to understand whether or not it is an appropriate label for what it purports to describe."
    Review sheet

  • Tao, P. K. and Gunstone, R. F. () The Process of Conceptual Change in Force and Motion during Computer-Supported Physics Instruction Journal of Research in Science Teaching: The Official Journal of the National Association for Research in Science Teaching 36 7


    Four computer simulation programmes, three of which were accompanied by predict-observe-explain format tasks designed to provoke cognitive conflict, were used to study the process of conceptual change for a sample of 27 10th Grade students at a Catholic Boys' High School in Melbourne, Australia. Students completed the programme collaboratively, in pairs, and were asked a Likert-type questionnaire after completion in order to gauge the students' views. Pre- and post-instruction testing was carried out, and students were interviewed following each of these stages.
    Review sheet

  • Halloun, I. A. and Hestenes, D. () Common sense concepts about motion American Journal of Physics 53 11


    This study surveyed and analysed the common sense beliefs on motion of a sample of 478 university physics students at Arizona State University using a multiple choice diagnostic test on the subject of mechanics. 22 students were randomly chosen for follow-up interviews. A taxonomy of common sense concepts which conflict with Newtonian theory was developed as a guide for instruction.
    Review sheet

  • Twigger, D.; Byard, M.; Driver, R.; Draper, S.; Hartley, R.; Hennessy, S.; Mohamed, R.; O'Mally, C.; O'Shea, T. and Scanlon, E. () The conception of force and motion of students aged between 10 and 15 years: an interview study designed to guide instruction International Journal of Science Education 16 2


    This study catalogued the responses of 36 students (16 girls and 20 boys) to 7 tasks on an example of motion in a particular context (e.g. kicking a pebble, a falling parachutist, and throwing a ball). The interviews lasted 1 hour and students participated in pairs, in order to encourage discussion. Students were also asked to give individual responses.
    Review sheet

  • 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.
    Review sheet

  • Klaassen, K.; Westra, A.; Emmett, K.; Ejkelhof, H. and Lijnse, P. () Introducing mechanics by tapping core causal knowledge Physics Education 43 4


    Review sheet

  • Watts, D. M. and Zylbersztajn, A. () A survey of some children's ideas about force Physics Education 16 6


    This study investigated the conceptions of force of a sample of 125 students aged 14. Data was collected using a multiple-choice-with-explanation questionnaire.
    Review sheet

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