A convex lens is a type of lens that is thicker at the center and thinner at the edges. It is also known as a converging lens because it converges parallel rays of light to a focal point.
The focal length of a convex lens can be found by using the formula: f = 1/(n-1)(1/r1 + 1/r2), where f is the focal length, n is the refractive index of the lens material, r1 is the radius of curvature of the first surface, and r2 is the radius of curvature of the second surface.
The focal length of a convex lens is directly proportional to the radius of curvature of its surfaces. This means that a lens with a smaller radius of curvature will have a shorter focal length, while a lens with a larger radius of curvature will have a longer focal length.
A convex lens can produce a magnified image by placing an object farther than the lens' focal length from the lens. This will create a virtual and enlarged image on the opposite side of the lens from the object.
Convex lenses have various applications in our daily lives, such as in eyeglasses, cameras, projectors, and telescopes. They are also used in scientific instruments, such as microscopes and spectacles, and in industrial equipment, such as lasers and barcode scanners.