Nagaland Board-2019

Draw a ray diagram and describe the image formation by a concave lens when an object is placed at (i) infinity (ii) a finite distance.

Where should an object be placed in front of a convex lens to get a real image of the size of the object? 

The change in focal length of an eye lens is caused by the action of the

An object $4 \mathrm{cm}$ in size is placed at $25 \mathrm{cm}$ in front of a concave mirror of focal length $15 \mathrm{cm}$. At what distance from the mirror should a screen be placed in order to obtain a sharp image? Find the size of the image.

A concave lens has focal length $15 \mathrm{cm}$. At what distance should the object from the lens be placed so that it forms an image at $10 \mathrm{cm}$ from the lens? Also find the magnification produced by the lens.

The type of mirror or lens used by dentist is _____.

The type of mirror or lens used in cameras is _____.

The type of mirror or lens used in a Rare view mirror of vehicles is _____.