Find the number of waves made by a Bohr’s electron in one comple...
Number of waves = n(n - 1)/2 where n = Principal quantum number or number of orbit number of waves = 3(3 - 1)/2 = 3 * 2/2 = 3
ALTERNATIVE SOLUTIONS :
In general, the number of waves made by a Bohr electron in an orbit is equal to its quantum number.
According to Bohr’s postulate of angular momentum, in the 3rd orbit
Mur = n h/2π
Mur = 3 (h/2π) …..(i) [n = 3]
According to de Broglie relationship
λ = h/mu ….(ii)
Substituting (ii) in (i), we get
(h/λ) r = 3 (h/2π) or 3λ = 2πr
[∵ mu = h/λ]
Thus the circumference of the 3rd orbit is equal to 3 times the wavelength of electron i.e. the electron makes three revolution around the 3rd orbit.
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Find the number of waves made by a Bohr’s electron in one comple...
The Bohr Model and Electron Waves
The Bohr model of the atom, developed by Niels Bohr in 1913, describes electrons as orbiting the nucleus in specific energy levels or shells. These shells are designated by integers (n=1, 2, 3, etc.), with larger values of n corresponding to higher energy levels. The electron in question is in the 3rd orbit, which means it is in the third energy level.
Electron Waves and Revolutions
According to quantum mechanics, electrons can also exhibit wave-like properties. Each electron in an atom can be described by a wave function, which represents the probability of finding the electron at a particular location.
In the context of the Bohr model, the electron can be visualized as a standing wave that wraps around the nucleus in its orbit. The wavelength of this standing wave is related to the electron's energy level and can be calculated using the formula:
λ = 2πr/n
where λ is the wavelength, r is the radius of the orbit, and n is the energy level.
Number of Waves in One Complete Revolution
To find the number of waves made by the electron in one complete revolution in its 3rd orbit, we need to determine the circumference of the orbit and divide it by the wavelength. The circumference of a circle can be calculated using the formula:
C = 2πr
where C is the circumference and r is the radius of the orbit.
Since the radius of the orbit is directly proportional to the energy level (n) in the Bohr model, we can rewrite the formula as:
C = 2πnr
Substituting the value of r from the wavelength formula:
C = 2πn(λ/2π)
The 2π terms cancel out, resulting in:
C = nλ
We can now determine the number of waves in one complete revolution by dividing the circumference by the wavelength:
Number of waves = C/λ = (nλ)/λ = n
Therefore, in the case of the electron in the 3rd orbit, the number of waves made in one complete revolution is 3.
Find the number of waves made by a Bohr’s electron in one comple...
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