When does a convex lens act like a magnifying glass?

Convex Lens as a Magnifying Glass

A convex lens acts like a magnifying glass when an object is placed in front of it at a distance less than its focal length. This arrangement allows the lens to produce a magnified image of the object for the observer. The magnification effect is a result of the way the convex lens converges light rays that pass through it.

Focal Length of a Convex Lens

The focal length of a convex lens is the distance from the center of the lens to the point where parallel rays of light converge or appear to diverge after passing through the lens. For a convex lens, the focal length is a positive value.

Magnification Formula

The magnification produced by a convex lens can be calculated using the magnification formula:

Magnification (m) = -(image distance)/(object distance)

When the object is placed within the focal length of the convex lens, the image formed is virtual, upright, and magnified. This magnified image is what makes the convex lens act like a magnifying glass, allowing the observer to see small details of the object more clearly.