(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A convex lens (f1=300mm) is placed 200 mm from a concave lens (f2=-50mm). An object is placed 6m away form the convex lens. (the order is as follows: object - 6m - convex lens - 200mm - concave lens).

Determine the position, magnification and nature of a final image.

2. Relevant equations

for a single lens:

1/x+1/y=1/f (where x is distance from the lens to the object, y is the distance from the lens to the image),

3. The attempt at a solution

Should I analyze 2 lenses separately?

At first first lens, which gives the image at y1:

1/6m+1/y1=1/300mm

y1=~31.5cm, so it is placed behind the second lens! Should I now consider the second lens, starting from the point, where is the image? I mean:

1/x2+1/y2=1/f2

where x2=20cm-31.5 cm=-11.5cm ?

I'm a little bit confused..

And finally, how to calculate the magnification?

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# Homework Help: 2 lenses

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