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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
State the law of radioactive decay.
Obtain the relation between the decay constant and half life of a radioactive sample.
A radioactive isotope has a half-life of T years. How long will it take the activity to reduce to a) 3.125%, b) 1% of its original value?
The Q value of a nuclear reaction 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.
\[\ce{^12_6C + ^12_6C ->^20_10Ne + ^4_2He}\]
Atomic masses are given to be
`"m"(""_1^2"H")` = 2.014102 u
`"m"(""_1^3"H")` = 3.016049 u
`"m"(""_6^12C)` = 12.000000 u
`"m"(""_10^20"Ne")` = 19.992439 u
Under certain circumstances, a nucleus can decay by emitting a particle more massive than an α-particle. Consider the following decay processes:
\[\ce{^223_88Ra -> ^209_82Pb + ^14_6C}\]
\[\ce{^223_88 Ra -> ^219_86 Rn + ^4_2He}\]
Calculate the Q-values for these decays and determine that both are energetically allowed.
Represent Radioactive Decay curve using relation `N = N_o e^(-lambdat)` graphically
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(b) A radioactive element reduces to 25% of its initial mass in 1000 years. Find its half life.
Define 'activity' of a radioactive substance ?
In a given sample, two radioisotopes, A and B, are initially present in the ration of 1 : 4. The half lives of A and B are respectively 100 years and 50 years. Find the time after which the amounts of A and B become equal.
In a radioactive decay, neither the atomic number nor the mass number changes. Which of the following particles is emitted in the decay?
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A source contains two species of phosphorous nuclei, \[\ce{_15^32P}\] (T1/2 = 14.3 d) and \[\ce{_15^33P}\] (T1/2 = 25.3 d). At time t = 0, 90% of the decays are from \[\ce{_15^32P}\]. How much time has to elapse for only 15% of the decays to be from \[\ce{_15^32P}\]?
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After 1 hour, `(1/8)^"th"` of the initial mass of a certain radioactive isotope remains undecayed. The half-life of the isotopes is ______.
What percentage of radioactive substance is left after five half-lives?
Which sample, A or B shown in figure has shorter mean-life?
Two radioactive materials A and B have decay constants \[6\lambda\] and \[2\lambda\] respectively. If initially they have same number of nuclei, then the ratio of the number of nuclei of A to that of B will be \[\frac{1}{\mathrm{e}}\] after time ______.
