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An electron is accelerated from rest through a potential difference of V volt. If the de Broglie wavelength of the electron is 1.227 × 10⁻² nm, the potential difference is:

1. 102 V
2. 103 V
3. 104 V
4. 10 V

Correct answer: 103 V

Solution

The de Broglie wavelength is given by λ = h / √(2meV), where h is Planck's constant, m is the mass of the electron, e is the charge of the electron, and V is the potential difference. Substituting the given wavelength and solving for V, we find V ≈ 103 V.

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