Two plane mirrors are at right angles to each other. $A$ man stands between them and combs his hair with his right hand. In how many images will he be seen using his left hand?

How will you decide whether a given piece of glass is a convex lens,concave lens or a plane glass plate?

$A$ convex mirror is used to form the image of a real object. Then tick the wrong statement.

$A$ child is standing in front of a magic mirror. She finds the image of her head bigger, the middle portion of her body of the same size, and that of the legs smaller. What is the order of combinations for the magic mirror from the top?

Sudha finds out that the sharp image of the window pane of her science laboratory is formed at a distance of $15\, cm$ from the lens. She now tries to focus the building visible to her outside the window instead of the window pane without disturbing the lens. In which direction will she move the screen to obtain a sharp image of the building? What is the approximate focal length of this lens?

$A$ plane mirror produces a magnification of