If an electron is accelerated through a potential difference of 54 volts, its de broglie wavelength will be:
Correct answer: B. 1.66 x 10^-10 m
- A. 1.66 x 10^-8 m
- B. 1.66 x 10^-10 m
- C. 1.66 x 10^-9 m
- D. 1.66 x 10^-12 m
Explanation
Option B is correct.Given data: h=6.63 x10^-34 Js, m=9.1x1 10^-31 kg, q= 1.6x10^-19 J ,V=54 vFind out: λ =?Solution ;Weknow thatλ =h/√2meV6.63 x10-34/ √ 2(9.1x1 10-31) (1.6x10-19)(54)1.66x10^-10 m
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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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