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MHT CET 2026 (17 Apr, Shift 1) · Matter Waves: de Broglie Wavelength

Matter Waves: de Broglie Wavelength question from MHT CET 2026 (17 Apr, Shift 1)

Q3MHT CET 2026 · 17 APR · SHIFT 1Easy

Matter Waves: de Broglie Wavelength

The kinetic energy of a free electron increases to 3 times the previous K.E. The ratio of new de- Broglie wavelength to previous de-Broglie wavelength is

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Answer: (a)

  1. λ=h2mK\lambda = \dfrac{h}{\sqrt{2mK}}, so λ∝1K\lambda \propto \dfrac{1}{\sqrt{K}}.
  2. K′=3K⇒λ′λ=K3K=13K' = 3K \Rightarrow \dfrac{\lambda'}{\lambda} = \sqrt{\dfrac{K}{3K}} = \dfrac{1}{\sqrt{3}}.
  3. So the answer is (a) 13\dfrac{1}{\sqrt{3}}.
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