Many students cannot correctly define 'an image’

Light, Sound and Waves


For example, some students believe images made by lenses can be in two places and/or lenses are not necessary to form images e.g. all objects will form an image.

Resources to Address This

  • Pinhole camera and lens camera (11-16)

    Ref - Practical Physics; Light and optics; Pinhole camera and lens camera; 

    Carrying out this series of activities will consolidate the idea of an image.  It also shows clearly the effect of a lens bringing together a series of images.

    View Resource


The following studies have documented this misconception:

  • Fetherstonhaugh, T. and Treagust, D. F. () Students’ Understanding of Light and Its Properties: Teaching to Engender Conceptual Change. Science Education, 76 (6),


    Review sheet

  • Kaltakci-Gurel, D., Eryilmaz, A. & McDermott, L. C. () Development and application of a four-tier test to assess pre-service physics teachers’ misconceptions about geometrical optics. Research in Science & Technological Education, 35 (2),


    Review sheet

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