What kind of mirror is behind the orange curtain?

Horizontal position of the object
-200 cm -5 cm
Check here to show multiple rays
Select the type of mirror and, if not a plane mirror, use the slider
to set the magnitude of the focal length, and then check your answer
Type of mirror: Plane mirror Converging mirror Diverging mirror
Magnitude of the focal length
30 cm 100 cm

Inspired by a 2002 article in The Physics Teacher by Melissa Dancy, Wolfgang Christian, and Mario Belloni.

Test your familiarity with mirrors. You can find the focal length of a converging or diverging mirror by calculating it, but see if you can get to the point where you can find it without doing a calculation.

Simulation first posted on 3-9-2018. Written by Andrew Duffy

Creative Commons License
This work by Andrew Duffy is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.
This simulation can be found in the collection at http://physics.bu.edu/~duffy/classroom.html.

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