Physics
posted by Sonia .
I have been working on this homework question for a bit, but I just can't get it. Please help me!
Where must an object be placed with respect to a convex lens (f=20cm) to generate an upright image that is 4 times as large as the object?
10 cm in front
10 cm behind
55 cm in fromt
55 cm behind
20 cm in front
20 cm behind
15 cm in front
15 cm behind
none listed
I think 55 cm in front, but I'm not sure.

15 cm in front
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