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The wavelength associated with an electron, accelerated through a potential difference of 100 V, is of the order of:

1. 1000 Å
2. 100 Å
3. 10.5 Å
4. 12 Å

Correct answer: 12 Å

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 values, the wavelength is approximately 12 Å.

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