# Physics lenses and mirrors- PLEASE CLARIFY

Hi everyone,
This is my understanding:
CONCAVE lens- diverges; smaller, virtual image (upright or inverted??)
CONVEX lens- converges; larger, real image (upright or inverted??)
CONCAVE mirror- converges; smaller, real image (upright or inverted??)
CONVEX mirror- diverges; larger, virtual image (upright or inverted??)

1. A real image is always inverted and virtual image is always upright, correct?
2. Why don't the reflected rays from a concave lens form the same image as a concave mirror? Or do they and it's just not as prominent because very little rays are reflected?
3. A concave lens forms a virtual image because it's rays never meet (diverge from each other), correct?
4. An object is always on the same side as the eye for a mirror (because you stand in front of a mirror). An object is on the opposite side as the eye for a lens (you look at an object through a lens). Is this correct? (I'm not talking about which side the image is on)
5. An object is + for both lens and mirror; the eye is + for mirror and – for lens. Is this correct?

This isn't really related to the above, but can you check if this is correct:
Shorter wavelength = higher frequency = more energy = bend more
If so, why does more energy lead to more bending? I know that more energy means a higher refractive index, but I don't understand this- please explain why in simple, practical terms.

Please don't explain laws or equations. I've searched the internet and textbooks to clarify and check my understand and all that provided was equations and laws so please simply read my description and comment on it.
Thank you!

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#### BerkReviewTeach

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This is my understanding:
CONCAVE lens- diverges; smaller, virtual image (upright or inverted??)
CONVEX lens- converges; larger, real image (upright or inverted??)
CONCAVE mirror- converges; smaller, real image (upright or inverted??)
CONVEX mirror- diverges; larger, virtual image (upright or inverted??)
For a converging system, lens or mirror, you can get many different types of images (inverted, real images that are larger, same size, or smaller as well as larger, upright, virtual images) depending on where the object is positioned. For a diverging lens or mirror, you always get a smaller, upright, virtual image.

1. A real image is always inverted and virtual image is always upright, correct?
2. Why don't the reflected rays from a concave lens form the same image as a concave mirror? Or do they and it's just not as prominent because very little rays are reflected?
3. A concave lens forms a virtual image because it's rays never meet (diverge from each other), correct?
4. An object is always on the same side as the eye for a mirror (because you stand in front of a mirror). An object is on the opposite side as the eye for a lens (you look at an object through a lens). Is this correct? (I'm not talking about which side the image is on)
5. An object is + for both lens and mirror; the eye is + for mirror and – for lens. Is this correct?
1. For a single mirror or a single lens, yes. For an optical device made of two or more lenses, mirrors, or both, the answer is not necessarily.