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a. Determine the 'effective focl length ...

a. Determine the 'effective focl length ' of the combination of the two lenses in Exercise 9.10, if they are placed 8.0 cm apart with their principal axes coincident . Does the answer depend on which side of the combination a beam of parallel light is incident? in the notion of effective focal length of this system useful at all ?

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The correct Answer is:
`-420` cm
0.98 cm
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