﻿ An electron microscope uses electrons accelerated through 50 kV. Find the de-Broglie wavelength of these electrons. If other factors like numerical aperture etc. are roughly the same, how does the resolving power of an electron microscope compare with that of an optical microscope which uses variable light? : Kaysons Education

# An Electron Microscope Uses Electrons Accelerated Through 50 KV. Find The De-Broglie Wavelength Of These Electrons. If Other Factors Like Numerical Aperture Etc. Are Roughly The Same, How Does The Resolving Power Of An Electron Microscope Compare With That Of An Optical Microscope Which Uses Variable Light?

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The de-Broglie wave length of V-volt ‘electron’ is given by

.

The mean wavelength of visible light may be taken to be , which is 105 times the wavelength of 50-kV electrons.

Now, the resolving power of a microscope is inversely proportional to the wavelength of the radiation used. Thus, the resolving power of electron microscope will be 105 times higher than that of optical microscope.

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