Why do they use a converging lens on a magnifying glass?

Question

Magnifying glass, converging lenses

Answer 1

converging lens forms a magnified and virtual image of an object situated close to the lens (between the focus point and the lens).

Answer 2

To better you understanding, it might help to prove it to yourself by carefully drawing a ray diagram for a hypothetical converging lens and object. Play with the diagrams and the numbers/formulas to show you how the object is magnified.

It is considerably difficult to draw such a think here on Yahoo Answers, so I leave the diagrams to you.

The formulas you might want to use are:
1/S + 1/S' = 1/f
where S and S' are the distances between the object and image respectively from the lens, and f is the focal length of the lens.

The magnification in height is the same as the ratio of the distances of the object/image from the lens. The sign on the height (it can potentially be negative in certain cases) indicated not a "negative height", but rather that the object is inverted.

Answer 3

Convex lenses can produce an upright, magnified image.

Answer 4

Because a diverging or concave lens would make the object appear smaller.