Electrons used in an electron microscope are accelerated by a voltage of 25 kV. If the voltage is increased to 100 kV, then the de Broglie wavelength associated with the electrons would:

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(2) decrease by 2 times. For an electron accelerated from rest through V: λ=h/(√2mₑ e V), so λ∝1/(√V). The voltage goes from 25 kV to 100 kV, a factor of 4. (λ₁)/(λ₂)=√(V₂)/(V₁)=√(100)/(25)=2. So λ₂=(λ₁)/2: the wavelength decreases by a factor of 2. That is why electron microscopes run at high voltage — a shorter wavelength resolves finer detail.

Electrons used in an electron microscope are accelerated by a voltage of 25 kV. If the voltage is increased to 100 kV, then the de Broglie wavelength associated with the electrons would:

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