what are concave and convex lenses
Concave and convex lenses are two types of lenses that refract light differently due to their shape. A convex lens is thicker at the center, causing parallel light rays to converge to a focal point, and is also known as a converging lens. A concave lens is thinner at the center, causing parallel light rays to diverge, and is also called a diverging lens.
Convex lens
Shape: Thicker at the center and thinner at the edges.
Function: Converges parallel light rays to a single focal point.
Focal Length: Positive.
Uses: Magnifying glasses, cameras, microscopes, and for correcting farsightedness (hypermetropia).
Concave lens
Shape: Thinner at the center and thicker at the edges.
Function: Diverges parallel light rays so they appear to spread out from a focal point.
Focal Length: Negative.
Uses: Binoculars, peepholes, and for correcting nearsightedness (myopia).