The ratio of the speed of the electrons in the ground state of hydrogen to the speed of light in vacuum is

1. 1/2                2. 2/137
3. 1/137            4. 1/237

Subtopic:  Bohr's Model of Atom |
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The transition from the state n = 4 to n = 3 in a hydrogen-like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition 
(a) 21                  (b) 32
(c) 42                  (d) 54

Subtopic:  Spectral Series |
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The hydrogen atom in the ground state is excited by monochromatic radiation of λ = 975 Å. The number of spectral lines in the resulting spectrum emitted will be :

1. 3

2. 2

3. 6

4. 10

Subtopic:  Spectral Series |
 62%
AIPMT - 2014
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X-ray is produced in a Coolidge tube at a given accelerating voltage. The wavelength of continuous X-rays has values from :

1.  Zero

2.  λmin to infinity and λmin>0

3.  λmin to λmax and 0<λmin<λmax<

4.  Zero to λmax and λmax<

Subtopic:  X-Ray (OLD NCERT) |
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The energy of the highest energy photon of Balmer series of hydrogen spectrum is close to
(1) 13.6 eV             

(2) 3.4 eV
(3) 1.5 eV               

(4) 0.85 eV

Subtopic:  Spectral Series |
 76%
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Taking Rydberg’s constant RH=1.097×107 m first and second wavelength of Balmer series in hydrogen spectrum is

(a) 2000 Å, 3000 Å                  (b) 1575 Å, 2960 Å
(c) 6529 Å, 4280 Å                  (d) 6552 Å, 4863 Å

Subtopic:  Spectral Series |
 63%
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The de-Broglie wavelength of an electron in the first Bohr orbit is 
(1) Equal to one fourth the circumference of the first orbit
(2) Equal to half the circumference of the first orbit
(3) Equal to twice the circumference of the first orbit
(4) Equal to the circumference of the first orbit

Subtopic:  Bohr's Model of Atom |
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The first line in the Lyman series has wavelength λ. The wavelength of the first line in Balmer series is

(1) 29λ             

(2) 92λ
(3) 527λ           

(4) 275λ

Subtopic:  Spectral Series |
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In Bohr model of hydrogen atom, the ratio of periods of revolution of an electron in \(n=2\) and \(n=1\) orbits is:
1. \(2:1\)             
2. \(4:1\)
3. \(8:1\)             
4. \(16:1\)

Subtopic:  Bohr's Model of Atom |
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In Bohr's model, the atomic radius of the first orbit is r0, then the radius of the third orbit is
(1) r09              

(2) r0
(3) 9r0               

(4) 3r0

Subtopic:  Bohr's Model of Atom |
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