One half of a convex lens of focal length 10cm is covered with a black paper. Can such a lens produce an image of a complete object placed at a distance of 30cm from the lens? Draw a ray diagram to justify your answer.
A convex lens can produce the complete image of the object even though half of the lens is covered. This is because light coming from the object can be refracted from the other half of the lens. However, the intensity of light will be reduced.