An electron and a proton are accelerated through the same potential. If their masses are "me" and "mp" respectively, then the ratio of their de-Broglie wave length is:
Correct answer: D. Option D
- A. Option A
- B. Option B
- C. Option C
- D. Option D
Explanation
Both gain the same kinetic energy (eV), so their de-Broglie wavelength depends only on mass:λ = h / √(2m eV)Taking the ratio:λₑ / λₚ = √(mₚ / mₑ)So the electron's wavelength is larger by the square root of the proton-to-electron mass ratio.
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Atoms emit or absorb light at specific wavelengths because electrons occupy quantized energy levels and change levels by absorbing or releasing photons. The topic covers emission and absorption spectra, spectral series, hydrogen’s line spectrum, energy-level transitions, and the relation between wavelength, frequency and photon energy.
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