Many students think of mass and weight as alternative words for the same property

Forces and Motion


Diagnostic Resources

The following worksheets may help to identify whether students hold this particular misconception.

For more information, see the University of York EPSE website.

Resource to Address This

  • Dan Smolski

    This resource will support classroom discussion on the difference between mass and weight.

    View Resource
  • More careful thinking about mass (11-14)

    Although the physics definition of mass is in terms of resistance to acceleration, we can see that this measure is directly linked to the amount of stuff idea, in that the more matter or stuff there is in an object, the harder it is to set into motion, or to stop.

    View Resource
  • Mass and weight (11-16)

    You cannot hope to clear up the great distinction between mass and weight by narrowing down the use of those common words. Nor can you exclude them or replace them in science. Students have to learn to live with their sloppy complexity.

    View Resource


The following studies have documented this misconception:

  • Brown, D. and Clement, J. () "Classroom Teaching Experiments in Mechanics" in R. Duit, F. Goldberg, & H. Niedderer (eds.), Research in physics learning - theoretical issues and empirical studies. San Diego State University, San Diego, CA.


    Review sheet

  • Dilber, R.; Karaman, I. and Duzgun, B. () High school students' understanding of projectile motion concepts. Educational Research and Evaluation, 15 (3),


    This study analysed a sample of 82 high school students (36 boys and 46 girls) between the ages of 16 and 17 using a qualitative multiple choice test on projectile motion. The test was administered both prior to and after a 4-week instructional period. The study took place in the department of physics at Ataturk University, Erzurum, Turkey.
    Review sheet

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