A lens and a convex mirror problem

AI Thread Summary
The problem involves a lens and a convex mirror, with a body positioned 40 cm from the lens and the lens 100 cm from the mirror. The lens has a focal length of 30 cm, leading to an image distance of 120 cm. This image then acts as a virtual object for the convex mirror, requiring a calculation of the new object distance, which is 20 cm. The discussion highlights the confusion regarding whether to treat the mirror as concave or convex, with the suggestion to use a negative object distance for the convex mirror. The solution requires further calculations to determine the final image distance and characteristics.
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Homework Statement


A body is positioned 40 cm from the left of a lens (f=30) and the lens is positioned 100cm left of a convex mirror (|R|=60), where will be the image and what type and magnitude will it have?


Homework Equations


1/u + 1/v = 1/f


The Attempt at a Solution


I tried to calculate the image after the lens - and got v = 120 cm.

Now, I don't know how to interpret the answer.
Can anyone help me out on this?

Thanks
 

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The convex mirror interrupt the rays to form the real image.
So (120 - 100) = 20 cm becomes the virtual object distance for the convex mirror. Now proceed.
 
That's my problem, now it is considered concave?
 
You can consider the mirror concave, and find the image distance that way, or you take it convex and use negative object distance.

ehild
 
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