plane mirror | convex mirror | concave mirror

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Many side mirrors on cars have a label that says "objects in mirror are closer than they appear." What type of mirror is it? The animation has an object and a mirror (position is given in meters and angle given in degrees). You can choose the type of mirror you want to try. Restart.

1. To determine what type of mirror a side mirror on a car is, first consider (from your experience) whether the image in the mirror is upright or inverted? Does your answer change as the object changes distance from the mirror? Therefore, which type of mirror can't it be?
2. For objects to be "closer than they appear," could it mean (1) that the image distance is longer than the object distance (so you perceive the object to be farther away) and/or (2) that the image is smaller (since we judge distances by relative sizes of objects). Therefore, which type of mirror can't it be (which mirror does not have a smaller image or a longer image distance)?
3. For the type of mirror that the car's side mirror is, then, why are "objects closer than they appear"?

Problem authored by Anne J. Cox.