Question

Light source in electron microscope is?

• A. Infra-red light
• B. Ultraviolet radiations
• C. Beam of electrons
• D. Cooled day light

Answer 1

Answer: (C)

Beam of electrons

• An electron microscope uses a beam of accelerated electrons as a source of Light (illumination).
  
• The wavelength of electrons is thousands of times shorter than visible light, Hence electron microscopes would be able to resolve objects that are thousands of times smaller.
• Resolution is the ability to distinguish two objects from each other.
• The electron microscope has a high-resolution power. This is due to the very low wavelength of the electron beam. Hence light source in the electron microscope is beam of electrons.
• So, the correct answer is 'Beam of electrons'.