1. Divide the amount of the substance at one point in time by the amount remaining after a period of time. The formula for calculating half life is as follows: t. 1/2. = t * ln(2)
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1. Suppose you know the proportions of a substance at two points in time. Denote the difference between these two points in time with the letter "T. Denote the ratio of the smaller
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Check the time between your first decay rate and when the decay rate reaches half this number.
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Relative decay rate k =  ln2/5272. The amount of Cobalt60 left after t years given by A(t) = A0e^kt) This implies A(1600) = 100e^ln2*1600/5272) = 81.0290 g.
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