The counting rate observed from a radioactive source at t=0 second was 1600 counts per second and at t=8 seconds it was 100 counts per second. The counting rate observed, as counts per second at t=6 seconds, will be

(a) 400                    (b) 300
(c) 200                    (d) 150

(c) A=A012tT1/2100=160012ST1/2T1/2=2 sec 

Again at t = 6 sec, A=16001262=200 counts/sec

Difficulty Level:

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  • 73%
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