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Set 13 of 16 · Questions 361-390 of 453

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JEE Main Physics · Atoms · Set 13 (Q361-390)

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  1. 361.
    The ratio of the energies of the electron in the hydrogen atom in the first and second excited states is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  2. 362.
    The activity of a radioactive material is 6.4 x curie. Its half life is 5 days. The activity will become 5 x curie after:
    1. (1)7 days
    2. (2)15 days
    3. (3)25 days
    4. (4)35 days
  3. 363.
    Light of two different frequencies whose photons have energies 1 eV and 2.5 eV respectively illuminate a metallic surface whose work function is 0.5 eV successively. Ratio of maximum speeds emitted electrons will be:
    1. (1)1 : 4
    2. (2)1 : 2
    3. (3)1 : 1
    4. (4)1 : 5
  4. 364.
    Speed of electron in its 1st Bohr's orbit is given by . If the time period of electron in th orbit is measured as 4.10 femto second, the value of is
    1. (1)1
    2. (2)2
    3. (3)3
    4. (4)4
  5. 365.
    An electron from various excited states of hydrogen atom emit radiation to come to the ground state. Let be the de-Broglie wavelength of the electron in the nth state and the ground state respectively. Let be the wavelength of the emitted photon in the transition from the nth state to the ground state. For large , (A, B are constants)
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  6. 366.
    The ratio of the shortest wavelength of Balmer series to the shortest wavelength of Lyman series for hydrogen atom is:
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  7. 367.
    The figure indicates the energy level diagram of an atom and the origin of six spectral lines in emission (e.g., line no. 5 arises from the transition from level to ). Which of the following spectral lines will occur in the absorption spectrum?
    1. (1)4, 5, 6
    2. (2)1, 2, 3, 4, 5, 6
    3. (3)1, 2, 3
    4. (4)1, 4, 6.
  8. 368.
    A nucleus of mass M at rest splits into two parts having masses and (M’ < M). The ratio of de Broglie wavelength of two parts will be:
    1. (1)1 : 2
    2. (2)2 : 1
    3. (3)1 : 1
    4. (4)2 : 3
  9. 369.
    The total energy of electron in the ground state of hydrogen atom is The kinetic energy of an electron in the first excited state is
    1. (1)6.8 eV
    2. (2)13.6 eV
    3. (3)1.7 eV
    4. (4)3.4 eV
  10. 370.
    For a hydrogen atom, the ratio of the largest wavelength of Lyman series to that of the Balmer series is
    1. (1)
    2. (2)27: 5
    3. (3)3: 4
    4. (4)
  11. 371.
    The diagram shows different transitions across the energy levels for an electron in a certain atom. Among these, which transition represents the emission of a photon with the most energy?
    1. (1)(II)
    2. (2)(I)
    3. (3)(IV)
    4. (4)(III)
  12. 372.
    Three energy levels of hydrogen atom and the corresponding wavelength of the emitted radiation due to different electron transition
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  13. 373.
    Hydrogen atom in ground state is excited by a monochromatic radiation of λ = 975 Å. Number of spectral lines in the resulting spectrum emitted will be:
    1. (1)3
    2. (2)2
    3. (3)6
    4. (4)10
  14. 374.
    During the transition of electron from state A to state C of a Bohr atom, the wavelength of emitted radiation is and it becomes when the electron jumps from state B to state C. Then the wavelength of the radiation emitted during the transition of electrons from state to state is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  15. 375.
    Given figure shows few data points in a photo electric effect experiment for a certain metal. The minimum energy for ejection of electron from its surface is (Planck’s constant h = 6.62 × J.s)
    1. (1)2.59 eV
    2. (2)2.27 eV
    3. (3)1.93 eV
    4. (4)2.10 eV
  16. 376.
    A beam of fast moving alpha particles were directed towards a thin film of gold. The parts and of the transmitted and reflected beams corresponding to the incident parts and of the beam are shown in the adjoining diagram. The number of alpha particles in
    1. (1) will be minimum and in minimum
    2. (2) will be minimum and in maximum
    3. (3) will be minimum and in maximum
    4. (4) will be maximum and in minimum
  17. 377.
    An electron bean is acceleration by a potential difference to hit a metallic target to produce rays. It produces continuous as well as characteristic X-rays. If is the smallest possible wavelength of X-ray in the spectrum, the variation of with is correctly represented in:
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  18. 378.
    An electron (mass m) with an initial velocity is moving in an electric field where is constant. If at t = 0 de Broglie wavelength is , then its de Broglie wavelength after time t is given by
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  19. 379.
    The energy levels of an atom is shown is figure. Which one of these transitions will result in the emission of a photon of wavelength 124.1 nm? Given (h = 6.62 x Js)
    1. (1)B
    2. (2)A
    3. (3)C
    4. (4)D
  20. 380.
    Hydrogen atom in ground state is excited by a monochromatic radiation of . Number of spectral lines in the resulting spectrum emitted will be
    1. (1)3
    2. (2)2
    3. (3)6
    4. (4)10
  21. 381.
    An alpha-particle of mass m suffers 1-dimensional elastic collision with a nucleus at rest of unknown mass. it’s scattered directly backwards losing, 64% of its initial kinetic energy. The mass of the nucleus is:
    1. (1)3.5 m
    2. (2)1.5 m
    3. (3)4 m
    4. (4)2 m
  22. 382.
    The figure shows the energy level of certain atom. When the electron deexcites from to , an electromagnetic wave of wavelength is cmitted. What is the wavelength of the electromagnetic wave emitted when the electron de excites from to E?
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  23. 383.
    The energy levels of an hydrogen atom are shown below. The transition corresponding to emission of shortest wavelength is
    1. (1)D
    2. (2)A
    3. (3)B
    4. (4)C
  24. 384.
    Which of the following figure represents the variation of with In A (If R = radius of a nucleus and A = its mass number)
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  25. 385.
    Some energy levels of a molecule are shown in the figure. The ratio of the wavelengths , is given by :
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  26. 386.
    Magnetic moment due to the motion of the electron in th energy state of hydrogen atom is proportional to.....
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  27. 387.
    Hydrogen atom from excited state comes to the ground by emitting a photon of wavelength . The value of principal quantum number 'n' of the excited state will be: (R: Rydberg constant)
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  28. 388.
    The radiation corresponding to transition of a hydrogen atom falls on a gold surface to generate photoelectrons. These electrons are passed through a magnetic field of . Assume that the radius of the largest circular path followed by these electrons is 7mm, the work function of the metal is:(Mass of electron = 9.1 x 10-31kg)
    1. (1)1.36eV
    2. (2)1.88eV
    3. (3)0.16eV
    4. (4)0.82eV
  29. 389.
    In Bohr's atomic model, the electron is assumed to revolve in a circular orbit of radius If the speed of electron is 2.2 x 106 m/s, then the current associated with the electron will be ___ x 10-2mA. [Take as ]
  30. 390.
    For hydrogen atom, and are the wavelengths corresponding to the transitions 1 and 2 respectively as shown in figure. The ratio of and is . The value of x is