Mathematical and Physical Journal
for High Schools
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Problem P. 4183. (September 2009)

P. 4183. The halflife of the radioactive isotope of lead, whose atomic mass number is 214, is 26.8 minutes. How long has it been decaying if only one-thousandth of the original atoms are present in the sample?

(4 pont)

Deadline expired on October 12, 2009.

Sorry, the solution is available only in Hungarian. Google translation

Megoldás. 267 perc, azaz kb. 4,5 óra.


143 students sent a solution.
4 points:121 students.
3 points:13 students.
2 points:3 students.
1 point:3 students.
0 point:2 students.
Unfair, not evaluated:1 solution.

Problems in Physics of KöMaL, September 2009