Physics Dawn of Modern Physics SZABMU 2023
PMDC Verified Question 18 of 52
The wavelength associated with an electron is of the order of:
A
Visible light
B
X-rays
C
Radio waves
D
Infrared
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option B: X-rays
Concept:

This addresses the fundamental scale of quantum mechanical matter waves for particles accelerated to practical laboratory energies.

Formula:

$$ \lambda = \frac{h}{\sqrt{2meV}} $$

Solution:

  • An electron accelerated through typically encountered potentials (tens to thousands of volts) achieves a de Broglie wavelength in the realm of \( 0.01 \text{ nm} \) to \( 1 \text{ nm} \).


  • This exact spatial dimension matches the wavelength of X-rays, making crystalline atomic structures excellent diffraction gratings for both X-rays and electrons.


Why other options are incorrect:

Visible, Infrared, and Radio waves represent macroscopic wavelengths (hundreds of nanometers to meters) that a high-speed fundamental particle does not naturally mimic.

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