Why Is My Calculation of Lens Object Distance Incorrect?

AI Thread Summary
The discussion revolves around calculating the object distance from a lens given that a real, inverted image is formed. An object is placed to the left of the lens, resulting in an image to the right that is half the size of the object, with a total distance of 102 cm between them. The formula used, m = -di/do, initially led to confusion regarding the signs and values for distances. The correct interpretation of the terms clarified the calculation, leading to a better understanding of the relationship between object distance and image distance. Ultimately, the participant resolved their misunderstanding and successfully applied the concepts to the problem.
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1.An object is placed to the left of a lens, and a real image is formed to the right of the lens. The image is inverted relative to the object and is one-half the size of the object. The distance between the object and the image is 102.0 cm.

(a1) How far from the lens is the object?



2.m=-(di/do)



3. with the equation above I thought it was just -1/2=120/do and solving for do gives -204 cm, but this answer is wrong, and so is 204. I know that m is negative because the image is inverted. Not sure if my logic is right or not, we haven't covered this yet in class but it is still on the homework.
 
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M = -q/p, in which q is the distance from the lens to the image and p is the distance from the lens to the object. The 102cm given is the distance between the object and image.
 
That worked, thanks. I had the wrong idea of what the terms actually meant.
 
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