A proton and an alpha particle are accelerated through the same potential difference. The ratios of their de broglie wavelengths λp/λa is:
Correct answer: B. 2√ 2
- A. 1
- B. 2√ 2
- C. 2
- D. 1√ 2
Explanation
λ = h/√ 2mqV λ∝ 1/√ mq λ p/λ a = √ ma x qa/mp x qp = √ 4mpx 2e/mpx e=√ 8 =2√ 2
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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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