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Karnataka Board PUCPUC Science Class 11

Find the Maximum Angular Speed of the Electron of a Hydrogen Atom in a Stationary Orbit.

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Question

Find the maximum angular speed of the electron of a hydrogen atom in a stationary orbit.

Sum
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Solution

Let the mass of the electron be m. 

Let the radius of the hydrogen's first stationary orbit be r.

Let the linear speed and the angular speed of the electron be v and ω, respectively.

According to the Bohr's theory, angular momentum (L) of the electron is an integral multiple of h/2 `pi`, where h is the Planck's constant.

`rArr mvr= (nh)/(2pi)` (Here , n is an integer)

V = rω

`⇒ mr^2 omega = (nh)/(2pi)`

`⇒  omega = (nh)/(2pixxmxxr^2)`

`therefore omega = (1xx(6.63xx10^34))/(2xx(3.14)xx(9.1093xx10^-31)xx(0.53xx10^-10)^2`

`= 0.413 xx 10^17  (rad)//s = 4.13 xx 10^16 (rad)//s`

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The Line Spectra of the Hydrogen Atom
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Chapter 21: Bohr’s Model and Physics of Atom - Exercises [Page 384]

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HC Verma Concepts of Physics Vol. 2 [English] Class 11 and 12
Chapter 21 Bohr’s Model and Physics of Atom
Exercises | Q 18 | Page 384

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