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The threshold wavelength for a metal surface whose photoelectric work function is 3.313 eV is:

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Important Questions on Modern Physics

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In the photochemical process, the rays which provide better resolution are_____.
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When four hydrogen nuclei combine to form a helium nucleus in the interior of sun, what amount of energy released per nucleon in this process?
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Nuclear fission is a reaction in which-
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Activity of radioactive element is decreased to one third of original activity R0 in 9 years. After further 9 years, its activity will be
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Which of the following are emitted by radioactive materials?
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The Sun radiates energy in all directions. The average radiation received on the earth surface from the Sun 1.4 kW/m2. The average Earth-Sun distance 1.5×1011 m. The mass lost by the Sun per day is (1 day=86400 s)
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Mx anti My denote the atomic masses of the parent and the daughter nuclei respectively, in radioactive decay. The Q value for a β--decay is Q1 and that for a β+-decay is Q2.
If me denotes the mass of an electron, then which of the following statements is correct?
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When a nucleus in an atom undergoes a radioactive decay, then the electronic energy levels of the atom