Long-sight defect could be corrected by using ____ lens:
a) concave
b) convex
c) diverging
d) none of theseΒ
People use concave lens for short-sight defect and convex lens for long-sight defect. They place convex lens in front of a hypermetropic eye, which moves the image and focuses it correctly on retina. Long-sight defect actually means difficulty in focusing on distant objects. Common name for this defect is myopia. Click here to know about the SI unit of charge.