Energy in joule (E) = charge × potential diff. in volt Eelectron =qcV and Eproton =qp4 V de-Broglie wavelength λ=Ph=2mEh λe=2 meeVh and λP=2 mee4 Vh(∵qe=qP) ∴λPλe=2 mPe4 Vh2 meeVh=2 meeV2 mPe4 V=2memP
Electrons are accelerated through a potential difference V and protons are accelerated through a potential difference 4 V. The de-Broglie wavelengths are λe and λp for electrons and protons respectively. The ratio of λpλe is given by: (given me is mass of electron and mp is mass of proton).
Held on 23 Apr 2013 · Verified 6 Jul 2026.
λpλe=memp
λpλe=mpme
λpλe=21mpme
λpλe=2memp
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