Two thin lenses of power +4 D and -2 D are in contact. What is

power 4d The power of a lens is +4D. Find the focal length of this lens. An object is placed at a distance of 50 cm from the optical centre of this lens. State the nature. Answer:the power of a convex lens is always positive. as you can see here the power is +4D, therefore the nature of the lens is that it is a convex lens. we know, P = 1f. also

power 4d, HMP 4D memiliki 4.