If electron and proton have same de broglie wavelength, which have greater speed?
Correct answer: A. Electron
- A. Electron
- B. Proton
- C. Both have same
- D. Electron and Proton cannot have wavelength
Explanation
Option A is correct.The electron is much lighter than the proton (approximately 1836 times lighter), for them to have the same momentum, the electron must have a greater velocity (speed) compared to the proton. This is because, for the same momentum, a lighter particle needs to move faster than a heavier particle. λ =h/pλ =h/mvv=h/mλ v∝ 1/m
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About Dawn of Modern Physics
Classical physics cannot explain blackbody radiation and related observations, leading to Planck’s quantum theory, in which energy is emitted or absorbed in discrete packets. Photons provide the particle model of light, with energy and momentum linked to frequency and wavelength, including the photoelectric effect and its threshold frequency.
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