2007-05-30 12:39:05 · 4 answers · asked by super_cat53 1 in Science & Mathematics ➔ Physics
After 1 half life, half remains
After 2 half lives, half of half (quarter remains)
After n half lives, (1/2)^n remains
2007-05-30 12:42:49 · answer #1 · answered by Anonymous · 0⤊ 1⤋
after 5 hrs, 1/2 remains
after 10 hrs, 1/4 remains (1/2 of 1/2)
after 15hrs, 1/8 remains (1/2 of 1/4)
so its 1/8.
2007-05-30 12:54:10 · answer #2 · answered by Anon Helper 3 · 0⤊ 1⤋
That's a trick question. 7/8ths of the original substance is converted to a different substance, but it is still there, except for the part that is converted to energy. You have to subtract the atomic weight of the new substance from that of the original substance to know how much is no longer there.
2007-05-30 13:00:02 · answer #3 · answered by Anonymous · 0⤊ 1⤋
(1/2)^(15/5) = (1/2)^3 = 1/8
2007-05-30 12:44:23 · answer #4 · answered by Helmut 7 · 0⤊ 1⤋