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The half-life of 146C is 5700 years. What does it mean ? Two radioactive nuclei X and Y initially contain an equal number of atoms. Their half lives are 1 hour and 2 hour respectively. Calculate the ratio of their rates of disintegration after two hours. |
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Answer» The half-life of 146C is 5700 years. It means that one half of the present number of radioactive nuclei of 146C will remain undecayed after 5700 years. Number of nuclei X after 2 hours, NX = N0(1/2) = N0/4 Number of nuclei Y after 2 hours, NY = N0(1/2)2/2 =N0/2 ∴ Ratio of rates of disintegration Rx/Ry = (N0/4)/N0/2 = 1/2. |
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