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→Finding Half Life and Count Rate
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1. Find the '''half life''' of this [[sample]] of [[radioactive]] [[isotope]].
:The '''half life''' of of this [[sample]] of [[radioactive]] [[isotope]] can be found by halving the initial count rate.
:5000/2 = 2500Bq
:The [[isotope]] took 3 [[minute]]s to half in [[Count Rate|count rate]]:
:'''Half life''' = 3 [[minute]]s.
2. Predict the [[Count Rate|count rate]] at 9 [[minute]]s.
:Since the '''half life''' is 3 [[minute]]s the [[Count Rate|count rate]] 3 [[minute]]s earlier can be halved.
:At 6 [[minute]]s the [[Count Rate|count rate]] was 1250Bq. Therefore at 9 [[minute]]s the [[Count Rate|count rate]] would be:
:1250/2 = 625Bq
3. Predict what the [[Count Rate|count rate]] was 2 [[minute]]s before the [[sample]] was first tested.
:Since the '''half life''' is 3 [[minute]]s the [[Count Rate|count rate]] 3 [[minute]]s later can be doubled.
:At 1 minute the [[Count Rate|count rate]] was 3968Bq. Therefore at -2 [[minute]]s the [[Count Rate|count rate]] would have been:
:3968x2= 7936Bq