Initially P→4N0 Q→N0 Half life Tp→1 min TQ→2min Let after time t number of nuclei of P and Q are equalie, 2t/14N0=2t/2N0 4222tt=2t/2=2t/2=2=4 min Disactive nucleus or Nuclei of R =(4N0−244N0)+(N0−22N0)=4N0−4N0+N0−4N0=5N0−2N0=29N0
Two radioactive nuclei P and Q, in a given sample decay into a stable nucleous R. At time t=0, number of P species are 4 N_0 and that of Q are N_0.…
NEET UG 2011 — Physics Modern Physics
2011mcqmedium
Two radioactive nuclei P and Q, in a given sample decay into a stable nucleous R. At time t=0, number of P species are 4N0 and that of Q are N0. Half-life of P (for conversion to R ) is 1 min where as that of Q is 2 min. Initially there are no nuclei of R present in the sample. When number of nuclei of P and Q are equal, the number of nuclei of R present in the sample would be
Official previous-year question
Held on 30 Apr 2011 · Verified 9 Jul 2026.
Options
- A
3N0
- B
29N0
- C
25N0
- D
2N0
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