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Question:

An electron is accelerated through a potential difference of 10,000 V. Its de Broglie wavelength is, (nearly) :(m_e = 9 × 10^-31 kg)

12.2 × 10^-12 m

12.2 × 10^-13 m

12.2 × 10^-14 m

12.2nm

Solution:

Correct option is B. 12.2 × 10^-12 m
For an electron accelerated through a potential V, λ=12.27√A˚=12.27 × 10^-10√10000 = 12.27 × 10^-12 m