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An electron is accelerated through a potential difference of 10,000 V. Its de Broglie wavelength is, (nearly: mₑ = 9.31 × 10⁻³¹ kg):

1. 12.2 × 10⁻¹³ m
2. 12.2 × 10⁻¹² m
3. 12.2 × 10⁻¹⁴ m
4. 12.2 nm

Correct answer: 12.2 × 10⁻¹² m

Solution

The de Broglie wavelength is calculated using λ = h / √(2mₑeV). Substituting h = 6.63 × 10⁻³⁴ J·s, mₑ = 9.31 × 10⁻³¹ kg, e = 1.6 × 10⁻¹⁹ C, and V = 10,000 V, we get λ ≈ 12.2 × 10⁻¹² m.

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