(a) Draw a labelled ray diagram showing the formation of a final image by a compound microscope at least distance of distinct vision.
(b) The total magnification produced by a compound microscope is 20. The magnification produced by the piece is 5. The microscope is focussed on a certain object. The distance between the objective and eyepiece is observed to be 14cm. If least distance of distinct vision is 20cm, calculate the focal length of the objective and the eye piece.

Explanation

Expression of magnifying power
`m=-(v_(0))/(u_(0))(1+(D)/(f_(e)))`
where, `v_(0)` is the image distance from the objective lens
`u_(0)` is the object distance from the objective lens D is the least distance of distinct vision `f_(c)` is the focal length of eye lens.