Lakhmir Singh Physics Class 10 Solutions Page No:249
Question 44: An object 50 cm tall is placed on the principal axis of a convex lens. Its 20 cm tall image is formed on the screen placed at a distance of 10 cm from the lens. Calculate the focal length of the lens.
Lakhmir Singh Physics Class 10 Solutions Page No:251
Question 1: If the image formed by a lens is always diminished and erect, what is the nature of the lens ?
Solution : Concave lens.
Question 2: Copy and complete the diagram below to show what happens to the rays of light when they pass through the concave lens :