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Dual Nature of Radiation and Matter question

2013 · Q138
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Dual Nature of Radiation and Matter question

2013 · Q138

NEETPhysicsDual Nature of Radiation and MatterMCQ+4 / −1
The de-broglie wavelength of neutrons in thermal equilibrium at temperature T is
  1. A
    3.08TA∘{{3.08} \over {\sqrt T }}\mathop A\limits^ \circT​3.08​A∘​
  2. B
    0.308TA∘{{0.308} \over {\sqrt T }}\mathop A\limits^ \circT​0.308​A∘​
  3. C
    0.0308TA∘{{0.0308} \over {\sqrt T }}\mathop A\limits^ \circT​0.0308​A∘​
  4. D
    30.8TA∘{{30.8} \over {\sqrt T }}\mathop A\limits^ \circT​30.8​A∘​
View written solutionFree

Correct answer: D

de Broglie wavelength of neutrons in thermal equilibrium at temperature T is

λ=h2mkBT\lambda = {h \over {\sqrt {2m{k_B}T} }}λ=2mkB​T​h​

= 6.63×10−342×1.67×10−27×1.38×10−23×T{{6.63 \times {{10}^{ - 34}}} \over {\sqrt {2 \times 1.67 \times {{10}^{ - 27}} \times 1.38 \times {{10}^{ - 23}} \times T} }}2×1.67×10−27×1.38×10−23×T​6.63×10−34​

= 30.8TA∘{{30.8} \over {\sqrt T }}\mathop A\limits^ \circ T​30.8​A∘​

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