In the electron microscope, electric & magnetic fields are used as_______________?
Correct answer: D. Converging source of electronsChoosing Binoculars For Bird Watching
- A. Electromagnetic gun
- B. Source of electromagnetic waves
- C. Deflecting charged particle
- D. Converging source of electronsChoosing Binoculars For Bird Watching
Explanation
Electric and magnetic fields in an electron microscope control and focus the moving electrons in much the same way that glass lenses focus light. They act as converging electron lenses, allowing a beam to be focused into a fine probe. Students may choose an electromagnetic gun because fields help produce and accelerate electrons, but their key optical role here is convergence.
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About Optics
Light is studied through reflection, refraction, dispersion, interference, diffraction and polarization, linking ray behavior with its wave nature. Questions may involve mirrors, lenses, optical instruments, refractive index and image formation, while geometrical optics deals with rays and wave optics explains effects such as interference and diffraction.
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