How to Solve a Converging Lens Problem?

AI Thread Summary
The discussion centers on a converging lens problem involving an object placed 20 cm from a lens with a 10 cm focal length. Participants agree that there is insufficient information to determine the image height since the object's height is not provided. They note that while the image height cannot be calculated, it can be expressed relative to the object height, such as being equal, double, or a fraction of it. One participant recalls a similar experience during their midterms, suggesting that the question may have intended to address magnification. The consensus is that without the object's height, a definitive answer cannot be reached.
kikko
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Homework Statement



There is an object 20 cm from a converging lens with a 10 cm focal length.

Homework Equations



Is the image upright or inverted?
Calculate the image distance.
Calculate the image height.

The Attempt at a Solution



I just had this on a college test in a testing center, I could find the first two with the thin lens equation and diagrams, not sure how I was supposed to get the last. I feel some info was missing, like object height. Any way my feeling was wrong?
 
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Your feeling wasn't wrong since there is not enough information to find the image height.For this question the image height equals the object height (magnification equals one) but the object height was not given.
 
Hi kikko.

I agree, there's not enough information for an absolute answer, but you could give a relative answer, like, 2 × the object height, or 1/3 the object height or the same as the object height.
 
Dadface said:
Your feeling wasn't wrong since there is not enough information to find the image height.For this question the image height equals the object height (magnification equals one) but the object height was not given.

its possible that they meant magnification, because i had a similar problem on midterms when i was in optics
 
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