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fluidistic
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Homework Statement
What should be the focal distance of a negative thin lens such that there's a virtual image situated at 50 cm from the lens, of an ant at 100 cm from the lens? Given that the ant is at the right side of the lens, localize and describe the image.
Homework Equations
1/f=1/s_o+1/s_i.
The Attempt at a Solution
Using the equation above I found that the focal distance is 33.33 cm.
Using my knowledge rather than math, the image is at the right of the lens (same side as the ant), it's virtual as they said and it's erect.
However I don't really like my description since I treated the ant as a point rather than a 2 dimensional object, hence the dislike of using the word "erect". It does not really make sense to me.
Is what I've done good?