What should be the position of an object relative to biconvex lens so that it behaves like a magnifying glass?

A card sheet divided into squares each of size 1 mm^2 is being viewed at a distance of 9 cm through a magnifying glass (a converging lens of focal length 10 cm) held close to the eye. What should be the distance between the object in converging lens and the magnifying glass if the virtual image of each square in the figure is to have an area of 6.25 mm^2 . Would you be able to see the squares distinctly with your eyes very close to the magnifier ?

The focal lengths of the objective and eye-piece of a compound microscope are 1.25 cm and 5 cm respectively. Find the position of the object relative to the objective in order to obtain an angular magnification of 30 in normal adjustment.

What does the path of an object look like when it is in uniform motion ?

A man with normal near point (25 cm) reads a book with small print using a magnifying glass: a thin convex lens of focal length 5 cm- What is the closest and the farthest distance at which he should keep the lens from the page so that he can read the book when viewing through the magnifying glass?

Under what conditions a concave lens can behave as a converging lens?

What is the apparent position of an object below a rectangular block of glass 6 cm thick ,if a layer of water 4 cm thick is on top of the glass?Given that a^mu_g=3//2 and a^mu_w = 4//3 . .

Where should an object placed from a conveging lens of focal length 20 cm,so as to obtain a real image of magnification 2?

Where should object be placed in front of a convex lens to get real image of the size of object?