A radioactive nucleus of mass M emits a photon of frequency v and the nucleus recoils. The recoil energy will be
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(a) Mc² – hv (b) h²v² / 2Mc² (c) zero (d) […]
The radioactivity of a certain material drops to 1/16 of the initial value in 2 hours. The half-life of this radio nuclide is
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(a) 10 min (b) 20 min (c) 30 min (d) […]
Which one of the following statements is true, if half-life of a radioactive substance is 1 month?
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(a) 7/8th part of the substance will disintegrate in 3 months (b) 1/8th part of […]
₉₂U²³⁵ undergoes successive disintegrations with the end product of ₈₂P²⁰³. The number of α and β-particles emitted are
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(a) α=8,β=6 (b) α=3,β=3 (c) α=6,β=4 (d) α=6,β=0
Correct Answer:
α=8,β=6
Explanation:
₉₂U²³⁵ → end […]
A radioactive sample S₁ having an activity of 5 μCi has twice the number of nuclei as another sample S₂ which has an activity of 10 μCi. The half lives of S₁ and S₂ can […]
The half-life period of a radio-active element X is same as the mean life time of another radio-active element Y. Initially they have the same number of atoms. Then
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(a) X and […]
In gamma ray emission from a nucleus
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(a) only the proton number changes (b) both the neutron number and the proton number change (c) there is no change in the proton number […]
Solar radiation is
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(a) transverse electromagnetic wave (b) longitudinal electromagnetic wave (c) both longitudinal and transverse electromagnetic waves (d) none of these
Correct Answer:
transverse electromagnetic wave
Explanation:
No explanation available. Be […]
The ‘rad’ is the correct unit used to report the measurement of
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(a) the rate of decay of radioactive source (b) the ability of a beam of gamma ray photons to produce […]
Ionization potential of hydrogen atom is 13.6 eV. Hydrogen atoms in the ground state are excited by monochromatic radiation of photon energy 12.1 eV. According to Bohr’s theory, the spectral lines emitted by hydrogen will […]
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