Discuss about simple microscope and obtain the equations for magnification for near point focusing and normal focusing.

Explanation

(i) A simple microscope is a single magnifying (converging) lens of small focal length. (ii) To get an erect, magnified and virtual image of the object, the object is placed between F and P on one side of the lens and viewed from other side of the lens. (iii) There are two magnifications for two kinds of focussing. (iv) The image is formed at infinity. (v) The angular magnification is defined as the ratio of angle `theta_i` subtended by the image with aided eye to the angle subtended by the object with unaided eye. (vi) This is the magnification for normal focusing (vii) The magnification for normal focusing is one less than that for near point focusing.