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Given wavelength of wave is 15800Å. If its wave number is X×10-1 cm-1. The value of X is (Nearest integer) 

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Important Questions on Atomic Structure

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The graph that depicts Einstein photoelectric effect for a monochromatic source of frequency above the threshold frequency is
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The magnitude of acceleration of the electron in the nth orbit of hydrogen atom is aH and that of singly ionised helium atom is aHe. The ratio aH:aHe is,

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The frequency for a series limit of Balmer and Paschen series respectively are f1 and f3. If the frequency of the first line of Balmer series is f2 then the relation between f1, f2 and f3 is
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A donor atom in a semiconductor has a loosely bound electron. The orbit of this electron is considerably affected by the semiconductor material but behaves in many ways like an electron orbiting a hydrogen nucleus. Given that the electron has an effective mass of 0.07 me, where me is mass of the free electron and the space in which it moves has a permittivity 13 ε0, then the radius of the electron's lowermost energy orbit will be close to (take, the Bohr radius of the hydrogen atom is 0.53 A°)
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The energies E1 and E2 of two radiations are 25 eV and 50 eV, respectively. The relation between their wavelengths i.e., λ1 and λ2 will be
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If the shortest wavelength in Lyman series of hydrogen atom is A, then the longest wavelength in Paschen series of He+ is
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In Balmer series for hydrogen atom, find the energy of photon corresponding to longest wavelength.
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For any given series of spectral lines of atomic hydrogen, let  Δv-=v-max-v-min  be the difference in maximum and minimum wave number in cm-1

The ratio Δv-Lyman/Δv-Balmar is

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In a Photoelectric effect experiment, frequency of incident radiation is increased by keeping other factors constant f>f0 .The stopping potential
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Which of the graphs shown below does not represent the relationship between incident light and the electron ejected from metal surface?
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The first member of the Balmer series of hydrogen atom has a wavelength of 6561 A. The wavelength of the second member of the Balmer series (in nm) is_____________
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Electromagnetic radiation of wavelength 663 nm is just sufficient to ionise the atom of metal A. The ionization energy of metal A in kJ mol-1 is ___. (Rounded-off to the nearest integer) h=6.63×10-34Js,c=3.00×108 ms-1, NA=6.02×1023 mol-1
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Taking the wavelength of first Balmer line in hydrogen spectrum (n=3  to n=2) as 660 nm , the wavelength of the 2nd Balmer line (n = 4  to  n = 2) will be :
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According to Bohr's theory, the time averaged magnetic field at the centre (i.e., nucleus) of a hydrogen atom due to the motion of electrons in the nth orbit is proportional to: (n= principal quantum number)
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The ratio of the shortest wavelength of two spectral series of hydrogen spectrum is found to be about 9. The spectral series are:
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In Balmer series, wavelength of first line is λ1 and in Brackett series wavelength of first line is λ2 then λ1λ2 is
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Calculate the energy in corresponding to light of wavelength 45 nm: (Planck’s constant h=6.63×10-34Js:speed of light c=3×108 ms-1)
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A photoelectric surface is illuminated successively by monochromatic light of wavelength λ and λ2. If the maximum kinetic energy of the emitted photoelectrons in the second case is 3 times that in the first case, the work function of the surface of the material is:
( h = Planck's constant, c = speed of light)
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A particular station of All India Radio, New Delhi, broadcasts on a frequency of 1,368 kHz (kilo Hertz). The wavelength of the electromagnetic radiation emitted by the transmitter is [speed of light, c=3.0×108 ms-1]
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The value of Planck's constant is 6.63×10-34 Js and the velocity of light is 3.0×108 ms-1. Which value is the closest to the wavelength in nanometers of a quantum of light, with a frequency of 8×1015 s-1?