Electrons in an electron microscope are accelerated through 25 kV. If voltage increases to 100 kV, their de Broglie wavelength will:
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Electrons in an electron microscope are accelerated through 25 kV. If voltage increases to 100 kV, their de Broglie wavelength will:

G1 Physics · Accepted Answer

For nonrelativistic acceleration, λ ∝ 1/√V. The voltage rises from 25 to 100 kV, i.e. factor 4; hence λ′/λ = 1/√4 = 1/2. Answer: A.