Answer to Question #167232 in Optics for Santosh

Question

Focal length of convex lens used for reading Hallmark916 on gold ornaments

Answer 1

A convex lens is also used as a simple microscope. The object is kept between the focal length and mirror so that a virtual, erect and magnified image is formed. Smaller focal length has more power and is suitable for larger magnification. Hence, convex lens of focal length 5 cm is preferred for reading Hallmark916 on gold ornaments.