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Question
What is the de Broglie wavelength of a dust particle of mass 1.0 × 10−9 kg drifting with a speed of 2.2 m/s?
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Solution
Mass of the dust particle, m = 1 × 10−9 kg
Speed of the dust particle, v = 2.2 m/s
Planck’s constant, h = 6.6 × 10−34 Js
De Broglie wavelength of the dust particle is given by the relation:
`lambda = h/(mv)`
= `(6.6 xx 10^-34)/(1 xx 10^(-9) xx 2.2)`
= 3.0 × 10−25 m
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