Engineering Board Exam Reviewer · Physics · hard
What is the de Broglie wavelength of an electron moving at 1 × 106 m/s? (h = 6.626 × 10-34 J· s, me = 9.109 × 10-31 kg)
- 7.27 nm
- 0.364 nm
- 1.455 nm
- 0.727 nm
Answer
D. 0.727 nm
Solution
= h/(mv) = 6.626 × 10-34/(9.109 × 10-31 × 106) = 7.274 × 10-10 m = 0.727 nm.
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