Explain the construction of simple microscope and derive its magnification power.

Explanation

Simple Microscope: Simple microscope is a convex lens of short focal length. It is held near the eye to get enlarged image of small objects. Let an object (AB) of height .h. is placed at a point within the principal focus (uMagnification power (M): Ratio of the height of the image produced by the microscope `(h_(2))` to the original height of the object(h) is called Magnification
`M=(A’B’)/(AB)`
Magnification `M =("height of the imagens" )/( "height of the object")=(h_(2))/(h_(1))`
Magnification can also be defined as the ratio of the distance of image (v) to the distance of object(u)
Magnification `M=("Distance of the image")/("Distance of the object")=(nu)/(u)`
Since the image is virtual and erect, the magnification (M) is taken as positive, In simple microscope, When the image is formed at the near point
`M=1+(D)/(f)`
When the image is formed at infinity
`M=(D)/(f)`
(ii) Write the uses of simple microscope.
(i) By watch repairers and jewellers.
(ii) To read small letters clearly.
(iii) To observe parts of flower, insects etc.
(iv) To observe finger prints in the field of forensic science.