Fingerprints are observed by the use of

The focal length of the objective and eye lenses of a microscope are $1.6 \, cm$ and $2.5 \, cm$ respectively. The distance between the two lenses is $21.7 \, cm$. If the final image is formed at infinity,what is the linear magnification?

$A$ simple microscope is used to see an object first in blue light and then in red light. Due to the change from blue to red light, what is the effect on its magnifying power?

$A$ compound microscope has two lenses. The magnifying power of one is $5$ and the combined magnifying power is $100$. The magnifying power of the other lens is

Which type of electromagnetic waves are used in an optical microscope? Why?

$A$ simple magnifying lens is used in such a way that an image is formed at $25 \, cm$ away from the eye. In order to have $10$ times magnification,the focal length of the lens should be