I wear hard contact lenses so its no big surprise to me that if you’re close enough, a concave mirror will magnify the pores on your face and your eyeballs.
To magnify your image in a concave mirror, you must place yourself within the mirror’s focal point. Using a ray diagram, you would see that this clearly results in a upright, larger, and virtual image. Which you can of course see in the mirror. Yay. Watch my guest Mr. Penguin from Kinetic Books: Principles of Physics demonstrate.
If you were behind the focal point of the mirror, your image would be real and inverted. If you were behind the center of curvature (which is a distance of 2f away from the mirror with f being the focal length), then your image would be smaller, rendering the “magnifying mirror” useless.
So I guess that contact lens wearers like me and makeup fanatics should appreciate this application of physics that we call the magnifying mirror. However, if you’re as sleepy as I am in the morning, even a gigantic image won’t stop you from inserting a contact lens into the wrong eye. Or even worse, inserting both into the same eye. Hmm…am I the only one who has done this more than once?
Twilit 