What is a lens? Distinguish between a convex lens and a concave lens. Which of the two is a converging lens: convex and lens or concave lens?
When does a convex lens behave as a concave lens ?
When does a convex lens behave as a concave lens ?
Which of the two diverges a beam of parallel rays of light : convex lens or concave lens ?
Concave lens and Convex lens
Ray coming from an object situated at infinity, fall on a convex lens and an image is formed at a distance of 16 cm from the lens. When a concave lens is kept in contact with the convex lens, the image is formed at a distance of 20 cm from the lens combination. Calculate the focal length of the concave lens.