NEET Physics Nuclei Questions Solved

PMT - 2010
In a radioactive substance at t =0, the number of atoms is 8×104, its half-life period is 3 yr. the number of atoms 1 x 10 will remain after interval (a) 9 yr (c) 6 yr [UP CPMT 2010] (b) 8 yr (d) 24 yr
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what is the respective number of α and β-particles emitted in the following radioactive decay 200 168 > (b) 6 and6 (d) 8 and 6 90 80 o'[1995] (a) 6 and8 (c) 8 and 8
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PMT - 1999
The half-life of radium is 1622 years. How long will i take for seven eighths of a given amount of radium to decay (A) 3244 years(B) 6488 years (C) 4866 years(D) 811 years (Raj. PMT 1999; AIEEEE 2004)
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The mass of proton is 1.0073 u and that of neutron is 1.0087 u (u = atomic mass unit) The binding energy of 2He4 is (mass of helium nucleus = 4.0015 u) (a) 28.4 Mev (c) 0.0305J [2003] (b) 0.061 u (d) 0.0305 erg
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The binding energies of the nuclei A and B are E, and Eb respectively. Three atoms of the element B fuse to give one atom of element A and an energy Qis released. Then E, Eb and Q are related as (a) E -3Eb Q
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A free neutron decays into a proton, an electron and (a) a beta particle (c) an antineutrino(d) a neutrino [1997] (b) an alpha particle
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In a radioactive sample the fraction of initial number of radioactive nuclei, which remains undecayed after n mean lives is (a) a (b) e
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The activity of a radioactive sample is measured as 9750 counts/min at t = 0 and as 975 counts/min at t-5 min. The decay constant is approximately (a) 0.922/min (c) 0.461/min 11997) (b) 0.691/min (d) 0.230/min
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The energy equivalent of one atomic mass unit is (a) 1.6 × 10-19 J (c) 931 Mev [1992] 23 (d) 9.31 Mev
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Solar energy is due to

1. fusion reaction

2. fission reaction

3. combustion reaction

4. chemical reaction

Q10:

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