The disintegration rate of a certain radioactive sample at any instant is 4250 disintegrations per minute. 10 minutes later, the rate becomes 2250 disintegrations per minute. The approximate decay constant is
(Take log101.88 = 0.274)
(Take log101.88 = 0.274)
0.02 min–1
2.7 min–1
0.063 min–1
6.3 min–1
The Correct Option is C
Solution and Explanation
\(A_0=4250\)
\(A=2250\)
\(A=A_0e^{−λt}\)
\(2250=4250e−λt\)
\(\frac {2250}{4250}=e^{−λt}\)
\(λ(10)=ln (\frac {4250}{2250})\)
\(λ(10)=0.636\)
\(λ=0.063\)
So, the correct option is (C): \(0.063\ min^{-1}\)
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Concepts Used:
Nuclei
In the year 1911, Rutherford discovered the atomic nucleus along with his associates. It is already known that every atom is manufactured of positive charge and mass in the form of a nucleus that is concentrated at the center of the atom. More than 99.9% of the mass of an atom is located in the nucleus. Additionally, the size of the atom is of the order of 10-10 m and that of the nucleus is of the order of 10-15 m.
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Following are the terms related to nucleus:
- Atomic Number
- Mass Number
- Nuclear Size
- Nuclear Density
- Atomic Mass Unit