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Burner
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Homework Statement
Two converging lenses with focal lengths of 40 cm and 20 cm are 10 cm apart. A 2.0-cm-tall object is 60 cm in front of the 40-cm-focal-length converging lens. a. Use ray tracing to find the position and height of the image. do this accurately with a ruler. Determine the answers by taking direct measurements on your diagram. b. Calculate the image position (with respect to the second lens, the one with focal length 20 cm) and height. Compare with your answers to part a.
Homework Equations
M = h'/h = s'/s
1/s + 1/s' = 1/f
The Attempt at a Solution
So far, I haved tried many times at the ray tracing part. This is just one page of my attempts: <link not available>.
As far as the calculation part is concerned, I have so far treated the the first, 40-cm focal length lens as if it were by itself. By applying the thin lens equation, the real image would be 120 cm away. However, since the second lens is in the way, that must be treated as a virtual image. Treating that as a the object for the second lens tells me that the it is now 24.4 cm away from the second lens, which is 14.4 cm away from the first lens. Using this as the object for the first lense gets me at -22.6 cm. And that's where I'm stuck at.
I have asked my professor about this problem, and he said that it was difficult, and upon trying it on the spot himself, seemed to have the same difficulties in ray tracing that I and other students were having.
I've also tried using this applet to no avail (since it's a web-based homework submission system, I get immediate feedback). I have only one try left on the web-based homework submission system before it'll prevents me from submitting any more.
Any tips would be greatly appreciated. Thanks!
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