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My Glasses

prettybird

Entry posted by prettybird

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When I was in ninth grade, my vision rapidly started to deteriorate. I went from perfect vision to not being able to read simple words more than 15 feet away. 

Glasses can be used to look at a few topics in physics, the first (and easiest) being how they stay on my nose. The force of friction between my nose and the glasses overcomes the force of gravity trying to pull my glasses of my face, and when they slide down my nose, the force of gravity is higher than the force of friction and so they slide slowly, as friction is still acting upon then, just with a kinetic coefficient of friction instead of static.

The other way that glasses can be looked at through a physics lens is with lenses. The reason a person would need glasses is that the eye cannot create a focal point at the retina in your eye, and so you see a blurry picture instead of a clear one. To correct this, a convex lens is used so that the focal point occurs on your retina and you can see clearly. Thicker lenses cause the focal point to be closer to the lens, and so if your eyes have more trouble focusing then you will have thicker lenses.

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Shadoof

Never really took the time to think about how glasses actually work. I see now that they just readjust the focal point of vision.

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SgtLongcoat

Isn't it possible that there are forces other than friction and gravity acting on the glasses when they start to slip? What about the forces of your face muscles, which you tend not to notice as they act subconsciously?

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prettybird
12 minutes ago, SgtLongcoat said:

Isn't it possible that there are forces other than friction and gravity acting on the glasses when they start to slip? What about the forces of your face muscles, which you tend not to notice as they act subconsciously?

Yeah, that's a good point. I would imagine that the force on the glasses from your nose and the muscles there would do a decent amount of work to combat the force of gravity. Thanks!

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