NEET Physics Nuclei Questions Solved


The count rate of a Geiger- Muller counter for the radiation of a radioactive material of half life of 30 minutes decreases to 5 s-1 after 2 hours. The initial count rate was

(a) 25 s-1               (b) 80 s-1
(c) 625 s-1              (d) 20 s-1

(b) A=A012t/T1/25=A0122×6030=A016A0=80 sec-1

Difficulty Level:

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