Which is the unit of power of a lens?

এই অধ্যায়ের আরও প্রশ্ন

• C-09-Q112What is a lens?
• C-09-Q113How can the nature (convex/concave) of a lens be identified without touching it?
• C-09-Q114Shiuli's spectacles have power D. The focal length of the lens is —
• C-09-Q115For Shiuli's D lens with an object placed 1 m away, the image formed will be —
• C-09-Q116A negative power lens (e.g. D) corresponds to a —
• C-09-Q117Which of the following best defines refraction of light?
• C-09-Q118A convex lens is called a converging lens because —
• C-09-Q119A mirage is formed because —
• C-09-Q120The focal length of a concave lens is taken as negative because —
• C-09-Q110The ray diagram usually used to draw the image for a convex lens uses — (i) parallel ray through focus, (ii) r