Optics mnemonic

[evoviiigsr]

I just thought of a way to remember a few things about mirrors. Just grab a metal spoon, one side is convex and the other is concave. No matter how close/far you move the spoon looking at the convex side, your image will be smaller and always upright, and there is no focal point where no image is formed. On the other side, your image is magnified and switches from upright to inverted as you move it away, disappearing momentarily at the focal point.

Or, you could just memorize it, this is more fun though. I'm surprised I wasn't taught this in physics class

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[vicinihil]

I remember what EK taught

EYE am POSITIVE that REAL is INVERTED (so your eye is always on the + and real side of a lens/mirror...and if an image shows up there with a positive value for Di...it's real and inverted)

Also conVEX and Divergent lens/mirror has negative focal lengths...I remember this as I'm VEXD that they have -f...stupid but does the trick

 

[evoviiigsr]

i thought that convex mirrors and converging lenses have negative focal lengths?

 

[BrokenGlass]

i thought that convex mirrors and converging lenses have negative focal lengths?

Concave mirrors and converging lenses have a positive focal length.

Convex mirror and diversing lenses have a negative focal length.

Concave mirrors are also called converging mirrors.

Convex mirrors are also called diverging mirrors.

Converging lenses are also called convex lenses (because the first interface the light strikes is convex.).

Diverging lenses are also called concave lenses (because the first interface the light strikes is concave).

Here is a quick way to remember it: for lenses, CONV goes with CONV. For mirrors, the opposite is true.

 

[FlowLimited]

i thought that convex mirrors and converging lenses have negative focal lengths?

Convex mirrors have negative focal lengths but converging (convex) lenses have positive focal lengths.

 

[axp107]

ALL you need to know about mirrors/lenses:

In a lens, is the image SUPPOSED to go thru? Yes. so if di is positive, its on the other side.

In a mirror, is the image SUPPOSED to go thru? No, its "supposed" to stay on the same side. so if di is positive, its on the same side

Convex mirrors and Diverging lenses: focal point is -ive

 

[BrokenGlass]

I just thought of a way to remember a few things about mirrors. Just grab a metal spoon, one side is convex and the other is concave. No matter how close/far you move the spoon looking at the convex side, your image will be smaller and always upright, and there is no focal point where no image is formed. On the other side, your image is magnified and switches from upright to inverted as you move it away, disappearing momentarily at the focal point.

Or, you could just memorize it, this is more fun though. I'm surprised I wasn't taught this in physics class

Old People Trapped In Childrens' Sweaters = OPTICS

 

[evoviiigsr]

Old People Trapped In Childrens' Sweaters = OPTICS

Thanks. Now when a passage about optics comes up on my MCAT, all that will go through my head as I dig around my neurons for information is an image of old people running around in chaos wearing children's sweaters that they can not take off...

 

[vicinihil]

u don't want them to take it off...right?...

 

[sunnyb32]

I just thought of a way to remember a few things about mirrors. Just grab a metal spoon, one side is convex and the other is concave. No matter how close/far you move the spoon looking at the convex side, your image will be smaller and always upright, and there is no focal point where no image is formed. On the other side, your image is magnified and switches from upright to inverted as you move it away, disappearing momentarily at the focal point.

Or, you could just memorize it, this is more fun though. I'm surprised I wasn't taught this in physics class

excellent -thanks

 

[petyr_baelish]

gr8