If N is the number of radioactive nuclei present at some instant, then N=N0e−λt The constant N0 represents the number of radioactive nuclei at t=0 Now, N2N1=e−λ2te−λ1tN2N1=e−λte−5λt=e−4λtN2N1=e1 but N2N1=e1 (as provided) Therefore, e1=e4λt1 or 4λt=1 or t=4λ1
Two radioactive materials X_1 and X_2 have decay constants 5 λ and λ respectively. If initially they have the same number of nuclei, then the ratio…
NEET UG 2008 — Physics Modern Physics
2008mcqeasy
Two radioactive materials X1 and X2 have decay constants 5λ and λ respectively. If initially they have the same number of nuclei, then the ratio of the number of nuclei of X1 to that of X2 will be e1 after a time
Official previous-year question
Held on 30 Apr 2008 · Verified 9 Jul 2026.
Options
- A
λ
- B
21λ
- C
4λ1
- D
λe
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