Question

An object is placed cm in front of converging lens . Find the focal length of lens if the magnification of object is/

Answer 1

pls provide the values of u and m

Answer 2

Full question: A person is viewing an extended object. If a converging lens is placed in front of his eye, will he feel that the size of object has increased? why?

1) A simple magnifier allows us to put the object closer to the eye than we could normally focus and forms an enlarged virtual images.

2) The principle behind this is angular magnification.

3) The magnification is Ma = 25/f for the close focus point, but since that causes eye strain, it is usually desirable to put the images at infinity giving Ma = 25/f.

4) So he feels the size of object increased. The reason is about mentioned.

5) Angular magnification : The ratio of the angle subtended at the eye by the image formed by an optical instrument to the angle subtended at the eye by the object being viewed.