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matej1408
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Homework Statement
I need to find optical power (reciprocal focal length) of this system with thin lens
Homework Equations
I tried to solve this using spherical diopter equation
n1/a+n2/b=(n2-n1)/R
where a is object distance and b is image distance
The Attempt at a Solution
equation for first diopter
n1/a+n/b'=(n-n1)/R
equation for second diopter
-n/b'+n2/b=-(n2-n)/R
adding these two equation i have
n1/a+n2/b=(2*n-n1-n2)/R
putting a→∞, b should be focal length then
so:
1/f=1/b=(2*n-n1-n2)/(n2*R)
but textbook solution is:
where -x=a and x'=b
i figured out this solution doesn't have two different focal length solutions (one from each side) and my solution have that. They solved problem using ray path and geometry.
I'm wondering what is wrong with my solution