I'm having a little problem with this question.. my brain is too small.(adsbygoogle = window.adsbygoogle || []).push({});

"A converging lens has a focal length of 10 cm. A screen is placed 30 cm from an object. Where should the lens be placed, in relation to the object, to produce a focused image?"

I've started with the formula

1/do + 1/di = 1/F

1/do + 1/di = 1/10

At this point I don't have a distance for do or di, because they're relative to the lens, and the lens position is the variable. Can someone push me in the right direction?

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# Homework Help: Simple lens equation problem

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