Question

A concave lens has focal length 15 cm. At what distance should the object from the lens
be placed so that it forms an image at 15 cm from the lens? Also find the magnification
produced by the lens.
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Answer 1

Answer:

Thus the object should be placed at a distance of 30 cm on the left side of the concave lens.

Linear magnification,

m=vu

=-10-30

=13.

Explanation:

hope you will help for this answer.

Answer 2

Answer:

Here, focal length of concave lens,

. object distance,

, image distance,

, magnification of lens,

As

Thus the object should be placed at a distance of 30 cm on the left side of the concave lens. <br> Linear magnification,

The positive sign of m shows that the image is virtual and erect, and its size is

of the size of the object.

Thus the object should be placed at a distance of 30 cm on the left side of the concave lens. Linear magnification, m=vu=-10-30=13.