How Far Are You From This Lens?

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The discussion revolves around a physics problem involving a lens that projects a magnified image of a person onto a wall. The image is three times the height of the person, and participants are trying to determine the object distance from the lens, the nature of the image (erect or inverted), and the focal length of the lens. It is clarified that a convex lens can produce a real image, and the magnification formula relates image distance and object distance. Participants emphasize the importance of correctly interpreting the problem and applying the lens formula to find the solution. The conversation highlights the collaborative effort to understand the concepts of optics and lens behavior.
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Homework Statement


You are standing in front of a lens that projects an image of you onto a wall 2.80 {\rm m} on the other side of the lens. This image is three times your height.
How far are you from the lens?
Is your image erect or inverted?
What is the focal length of the lens?
Is the lens converging or diverging?

Homework Equations



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The Attempt at a Solution


none

thanks a lot for your help
 
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Which lens produces real magnified image?
What is the realtion between the objectg distsnce, image distance and magnification?
 


well the convex len can produce a real image, and m=-image distance/ object distance. i have try everything, and i don't know why it keep tell me i am wrong, if you don't mind can you do one of the part, then i can check it? thanks a lot for your help
 


Image distance is given. Magnification is given. Find the object distance.
Use the formula
1/do + 1/di = 1/f
For real image di is +ve.
And for virtual image di is -ve.
 


oh ok, thanks a lot. i think i misread the question first. thanks so much for your help
 

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