Optics - combination of lenses/mirrors

[dartmed]

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I know what happens when you have a converging/diverging system, but when it comes to combination of mirrors/lenses, I am lost. Are there any tricks as to when you add two more concave mirrors or convex lenses or a mirror and a lens?

If so, can someone please help me. My test is tomorrow- and this and thin-lens are things that I am just unsure of. Thanks!!!

 

[nashaiy]

I know what happens when you have a converging/diverging system, but when it comes to combination of mirrors/lenses, I am lost. Are there any tricks as to when you add two more concave mirrors or convex lenses or a mirror and a lens?

If so, can someone please help me. My test is tomorrow- and this and thin-lens are things that I am just unsure of. Thanks!!!

Multiple lens or mirror systems can get a bit complicated and are unlikely to be tested except for conceptually. However, if they are, just separate the first lens/mirror and look at it by itself and what image it creates. Then take that image as the object for the next lens/mirror to find the final image. I doubt there are any tricks because the first object could be within the focal length or outside of the focal length of a first lens/mirror and then the first image created could be within or outside of the focal length of the next lens/mirror. The only thing to keep in mind is that the image created by the first lens/mirror is the object for the next BUT the object distance for the second lens/mirro can now be negative depending on where the first image was created. This is a big exception as we have always leaned that object distances are positive. I hope that helps.

 

[dontbeanegaton]

Just remember that there really aren't many multi-step problems on the MCAT. If there is a multi-optics problem, there is something you usually have to just notice.
For example, if a converging mirror sits in front of a flat mirror, the image distance (i) - the dist. between mirrors gives you the distance from the flat mirror of image formation.