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Question
What is the de Broglie wavelength of a bullet of mass 0.040 kg travelling at the speed of 1.0 km/s?
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Solution
Mass of the bullet, m = 0.040 kg
Speed of the bullet, v = 1.0 km/s = 1000 m/s
Planck’s constant, h = 6.6 × 10−34 Js
De Broglie wavelength of the bullet is given by the relation:
`lambda = h/(mv)`
= `(6.6 xx 10^(-34))/(0.040 xx 1000)`
= 1.65 × 10−35 m
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