∴Image distance for theeyepiece, v2 = −25 cm
Object distance for the eyepiece = u2
According to the lensformula, we have the relation:
Image distance for the objective lens,
Object distance for the objective lens= u1
According to the lensformula, we have the relation:
Magnitude of the object distance, 
= 2.5 cm
The magnifying power of acompound microscope is given by the relation:
Hence, the magnifyingpower of the microscope is 20.
(b) The final image is formedat infinity.
∴Imagedistance for the eyepiece,
Object distance for the eyepiece = u2
According to the lensformula, we have the relation:
Image distance for the objective lens,
Object distance for the objective lens= u1
According to the lensformula, we have the relation:
Magnitude of the object distance, = 2.59 cm
The magnifying power of acompound microscope is given by the relation:
Hence,the magnifying power of the microscope is 13.51.