Calculating Object-Lens Distance for Diverging Lens Optics

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The discussion revolves around calculating the object-lens distance for a diverging lens with a focal length of 6mm and an image magnification of 0.5. A participant initially calculated the distance as 18mm using the lens maker formula and the magnification ratio but found this incorrect. The correct distance between the object and the lens is determined to be 6mm. The importance of careful sign management in the calculations is emphasized. Ultimately, the issue was resolved with assistance from another participant.
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Diverging lens has focal length 6mm and image magnification 0.5. What is the distance between object and lens?

I used the fact that distance image to lens/distance object to lens = 0.5 and the lens maker formula with f=-6 and combined the two formula but this gives distance = 18mm, when answer is in fact 6mm.
Where have I gone wrong?
 
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slaw155 said:
Diverging lens has focal length 6mm and image magnification 0.5. What is the distance between object and lens?

I used the fact that distance image to lens/distance object to lens = 0.5 and the lens maker formula with f=-6 and combined the two formula but this gives distance = 18mm, when answer is in fact 6mm.
Where have I gone wrong?

Show your work. Take care of the signs.

ehild
 
thanks solved it
 
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