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Mere Teacher · Previous Year Questions
NEET Physics · Atoms · Set 13 (Q361-390)
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361.
To explain his theory, Bohr used
(1)conservation of linear momentum
(2)quantization of angular momentum
(3)conservation of quantum frequency
(4)none of these
362.
The minimum energy required by a hydrogen atom in ground state to emit radiation in Balmer series is nearly:
(1)1.5eV
(2)13.6eV
(3)1.9eV
(4)12.1eV
363.
The graph which depicts the results of Rutherford gold foil experiment with α-particles is: α-particles is: Y = Number of scattered α-particles detected (Plots are schematic and not to scale)
(1)
(2)
(3)
(4)
364.
The most penetrating radiation out of the following are
(1)β ‐rays
(2)γ ‐rays
(3)X ‐rays
(4)α ‐rays
365.
The mass of proton, neutron and helium nucleus are respectively 1.0073 u, 1.0087 u and 4.0015u. The binding energy of helium nucleus is:
(1)142 MeV
(2)28.4MeV
(3)56.8 MeV
(4)7.1 MeV
366.
Which rays contain (positive) charged particles?
(1)α ‐rays
(2)β ‐rays
(3)γ ‐rays
(4)X ‐rays.
367.
Nucleus A is having mass number 220 and its binding energy per nucleon is 5.6 MeV. It splits in two fragments ′B′ and 'C' of mass numbers 105 and 115. The binding energy of nucleons in 'B′ and 'C' is 6.4 MeV per nucleon. The energy Q released per fission will be:
(1)0.8 MeV
(2)275 MeV
(3)220 MeV
(4)176 MeV
368.
Which source is associated with a line emission spectrum?
(1)Electric fire
(2)Neon street sign
(3)Red traffic light
(4)Sun
369.
The constituents of atomic nuclei are believed to be
(1)neutrons and protons
(2)protons only
(3)electron and protons
(4)electrons, protons and neutrons
370.
In a Ruby laser, the colour of laser light is due to atom.
(1)oxygen
(2)aluminium
(3)xenon
(4)chromium
371.
2 α− particle consists of
(1)2 protons only
(2)2 protons and 2 neutrons only
(3)2 electrons, 2 protons and 2 neutrons
(4)2 electrons and 4 protons only
372.
Number N of the αparticles deflected in Rutherford a scattering experiment varies with the angle of deflection θ. Then the graph between the two is best represented by.
(1)
(2)
(3)
(4)
373.
Hydrogen atoms are excited from ground state of the principle quantum number 4. Then the number of spectral lines observed will be
(1)3
(2)6
(3)5
(4)2
374.
The ground state energy of hydrogen atom is ‐13.6 eV. When its electron is in the first excited state, its excitation energy is
(1)10.2 eV
(2)0
(3)3.4 eV
(4)6.8 eV
375.
In a radioactive decay chain, the initial nucleus is 90232Th. At the end there are 6α-particles and 4 β-particles which are emitted. If the end nucleus is ZAX,A and Z are given by :
(1)A=202;Z=80
(2)A=208;Z=80
(3)A=200;Z=81
(4)A=208;Z=82
376.
How many alpha and beta particles are emitted when Uranium 92U238 decays to lead 82Pb206?
(1)3 alpha particles and 5 beta particles
(2)6 alpha particles and 4 beta particles
(3)4 alpha particles and 5 beta particles
(4)8 alpha particles and 6 beta particles
377.
The explosive in a Hydrogen bomb is a mixture of 1H2,1H3 and 3Li6 in some condensed form. The chain reaction is given by 3Li6+0n1→2He4+1H3 1H2+1H3→2He4+0n1 During the explosion the energy released is approximately [Given : M(Li)=6.01690amu, M(H2)=2.01471amu, M(2He4)=4.00388amu, and 1amu=931.5MeV]
(1)28.12MeV
(2)12.64MeV
(3)16.48MeV
(4)22.22MeV
378.
Positron is the antiparticle of
(1)proton
(2)electron
(3)neutron
(4)photon
379.
α-particle consists of:
(1)2 protons only
(2)2 protons and 2 neutrons only
(3)2 electrons, 2 protons and 2 neutrons
(4)2 electrons and 4 protons only
380.
The atomic number of silicon is 14. Its ground state electron configuration is
(1)1s22s22p22s4
(2)1s22s22p63s13p3
(3)1s22s22p83s2
(4)1s22s22p63s23p2
381.
In Bohr's atomic model of hydrogen, let K. P and E are the kinetic energy, potential energy and total energy of the electron respectively. Choose the correct option when the electron undergoes transitions to a higher level:
(1)All K. P and E increase.
(2)K decreases. P and E increase.
(3)P decreases. K and E increase.
(4)K increases. P and E decrease.
382.
From the statements given below:(A) The angular momentum of an electron in nth orbit is an integral multiple of h.(B) Nuclear forces do not obey inverse square law.(C) Nuclear forces are spin dependent.(D) Nuclear forces are central and charge independent.(E) Stability of nucleus is inversely proportional to the value of packing fraction. Choose the correct answer from the options given below:
(1)(A), (B), (C), (D) only
(2)(A), (C), (D), (E) only
(3)(A), (B), (C), (E) only
(4)(B), (C), (D), (E) only
383.
In Rutherford experiment, for head-on collision of α-particles with a gold nucleus, the impact parameter is
(1)of the order of 10−10m
(2)zero
(3)of the order of 10−6m
(4)of the order of 10−14m
384.
The transition from the state n=3 to n=1 in a hydrogen like atom results in ultraviolet radiation. Infrared radiation will be obtained in the transition from
(1)2→1
(2)3→2
(3)4→2
(4)4→3
385.
Due to earth’s magnetic field, the charged cosmic rays particles
(1)can never reach the pole
(2)can never reach the equator
(3)require greater kinetic energy to reach the equator than pole
(4)require less kinetic energy to reach the equator than pole.
386.
Which one of the following is NOT correct?
(1)In forward biased condition diode conducts.
(2)If the packing fraction is negative, the element is stable.
(3)Binding energy is the energy equivalent to mass defect.
(4)Radioactive element can undergo spontaneous fission.
387.
The scientist who is credited with the discovery of 'nucleus' in an atom is
(1)Niels Bohr
(2)Rutherford
(3)J.J. Thomson
(4)Balmer
388.
The number of spectral lines emitted by atomic hydrogen that is in the 4th energy level, is
(1)3
(2)1
(3)6
(4)0
389.
Consider the following radioactive decay process 84218AαA1β−A2γA3αA4β+A5γA6 The mass number and the atomic number A6 are given by:
(1)210 and 82
(2)210 and 84
(3)210 and 80
(4)211 and 80
390.
In a photoelectric effect experiment, the graph of stopping potential V versus reciprocal of wavelength obtained is shown in the figure. As the intensity of incident radiation is increased