A1 A2 N1−N2=λN1=λN2=[λA1−A2]
The decay constant of a radio isotope is λ. If A1 and A2 are its activities at times t1 and t2 respectively, the number of nuclei which have decayed during the time (t1−t2)
Held on 30 Apr 2010 · Verified 9 Jul 2026.
A1t1−A2t2
A1−A2
λ(A1−A2)
λ(A1−A2)
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