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प्रश्न
Draw a graph showing the variation of decay rate with number of active nuclei.
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उत्तर
According to Rutherford and Soddy's law for radioactive decay = `(-dN)/(dt) = λN`
where decay constant (λ) is constant for a given radioactive material. Therefore, the graph between N and `(dN)/(dt)` is a straight line as shown in the diagram.
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संबंधित प्रश्न
The Q value of a nuclear reaction \[\ce{A + b → C + d}\] is defined by
Q = [ mA+ mb− mC− md]c2 where the masses refer to the respective nuclei. Determine from the given data the Q-value of the following reactions and state whether the reactions are exothermic or endothermic.
\[\ce{^1_1H + ^3_1H -> ^2_1H + ^2_1H}\]
Atomic masses are given to be
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`"m"(""_1^3"H")` = 3.016049 u
`"m"(""_6^12"C")` = 12.000000 u
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\[\ce{^223_88Ra -> ^209_82Pb + ^14_6C}\]
\[\ce{^223_88 Ra -> ^219_86 Rn + ^4_2He}\]
Calculate the Q-values for these decays and determine that both are energetically allowed.
A radioactive nucleus 'A' undergoes a series of decays as given below:
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(a) Derive the relation between the decay constant and half life of a radioactive substance.
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