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Question
An electron in an atom is revolving round the nucleus in a circular orbit of radius 5.3 × 10-11 m with a speed of 3 × 106 m/s. Find the angular momentum of electron.
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Solution
Given,
r = 5.3 × 10-11 m
v = 3 × 106 m/s
m = 9.1 × 10-31 kg
L = ?
Angular momentum of electron is
L = m v r
= 9.1 × 10-31 × 3 × 106 × 5.3 × 10-11
= 1.447 × 10-34 kg m2/s
∴ Angular momentum of electron is 1.447 × 10-34 kg m2/s.
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