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A convex lens of +9 D is pressed against a concave lens… | StemPy Lab
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A convex lens of +9 D is pressed against a concave lens of -4 D. What is the focal length of the pair?
Physics
Medium
High School (11–12)
Optics
Created by
StemPy Lab
A convex lens of
+
9
+9
+
9
D is pressed against a concave lens of
−
4
-4
−
4
D. What is the focal length of the pair?
7.7
cm
7.7\ \text{cm}
7.7
cm
11.1
cm
11.1\ \text{cm}
11.1
cm
20
cm
20\ \text{cm}
20
cm
25
cm
25\ \text{cm}
25
cm
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