A radium watch dial contained 20 micrograms of radium-226 in the year 2000. The watch was discovered by archeologists in the future and found to contain only 5 micrograms of radium-226. In about what future year was the watch discovered?
2007-12-14 05:29:44 · 2 answers · asked by Anonymous in Science & Mathematics ➔ Chemistry
What fraction of original Ra remains? How many halvings?How many half-lives?
(I wonder what life will be like in 5240)
2007-12-14 05:48:54 · answer #1 · answered by Facts Matter 7 · 0⤊ 0⤋
y=(y preliminary volume)e^kt with the help of definition, a million/2 yia=yiae^kt, kt =ln(a million/2)=-ln(2) 1620k=-ln2, ok=-ln2/1620, ok=-.000428, then 30=150e^-.000428t 30/a hundred and fifty = e^-.000428t ln(30/a hundred and fifty)=-.000428t -ln5=-.000428t -a million.60944/-.000428 = t t=3760.37years
2016-12-11 04:40:31 · answer #2 · answered by ? 4 · 0⤊ 0⤋