Understanding Virtual Images in Lenses and Mirrors

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A stamp collector uses a converging lens with a focal length of 32 cm to view a stamp located 17 cm in front of the lens, resulting in a virtual image. The calculation using the lens formula confirms that the image distance (di) is -32.267 cm, indicating a virtual image since it is negative. The discussion raises confusion about the terminology of "front" and "behind" regarding lenses, suggesting that "behind" for the viewer corresponds to "in front" of the lens. Clarification is sought on the perspective of image location in relation to the viewer's position. Understanding these concepts is crucial for accurately interpreting virtual images in optics.
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1. A stamp collector uses a converging lens with focal length 32 cm to view a stamp 17 cm in front of the lens.

Where is the image located?
a. in front of the lens (real image)
b. behind the lens (virtual image)


2. 1/f = 1/do + 1/di


3. 1/32 = 1/17 + 1/di
di = -32.267 cm

Because it's negative it is a virtual image.

For this problem, I imagined

front behind
---f--do---lens-----------

A virtual image is in the same side as the object. So something like this:
http://www.pa.msu.edu/courses/2000fall/PHY232/lectures/lenses/virtual_image.gif


So then why does the answer say if its virtual it is behind the lens? Also, what is considered front/behind for lens/mirrors?
 
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I think it is referring to the viewer. Behind the lens for the viewer is in front for the lens.
 
Thank You!
 
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