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Grade 12th PassModern Physics

Suppose a radioactive material has 10 atoms initially. So after 1st half life its no. of atoms will become 5 but what will happen after the 2nd half life. How can it be 2.5 ???

Profile image of Pramit Rana
14 Years agoGrade 12th Pass
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1 Answer

Profile image of Chetan Mandayam Nayakar
14 Years ago

as you will be aware, N=Noe-λt. THIS DOES NOT IN ANY WAY SAY THAT AFTER TIME 't',   EXACTLY  Noe-λt ATOMS WILL NOT HAVE DECAYED. IT MERELY STATES THAT AFTER TIME 't', the PROBABILISTIC EXPECTATION OF THE NUMBER OF ATOMS THAT HAVE NOT DECAYED IS Noe-λt. It even applies to the case where only one undecayed atom is remaining.