An angular magnification (magnifying power) of `30 X` is desired using an objective of focal length `1.25 cm` and an eye piece of focal length `5 cm`. How will you set up the compound microscope ?

Explanation

`m_(e)=1+25//5=6`
`m_(0)=30//m_(e)=5`
`m_(0)=v_(0)//-u_(0)v_(0)=-5u_(0)`
`1//f_(0)=1//v_(0)-1//u_(0)f_(0)=-(5//6)u_(0)`
`u_(0)=1.5 cm, v_(0)=7.5cm`
`u_(e)=-4.17cm`
Length of the tube `=u_(e)+v_(0)=11.67cm`