An electron is accelerated from rest through a potential difference $V$. Its de Broglie wavelength (in Å) is approximately $12.27/\sqrt{V}$. For $V = 150$ V, rounded $\lambda$ (in tenths of Å, i.e. $10\lambda$) is:
Answer (integer)
10
Solution
$\lambda = 12.27/\sqrt{150} \approx 12.27/12.25 \approx 1.0$ Å; $10\lambda \approx 10$.
About this question
Subject: Physics · Chapter: Dual Nature of Matter and Radiation · Topic: de Broglie Hypothesis
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