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Question 128892: I have a questions dealing with Logarithmic functions. The question I am dealing with is:
We have all heard of carbon dating. Materials are tested for c14 to determine how long ago they lived. Here is how it works. Cosmic ray bombardment of the atmosphere produces neutrons, which in turn react with nitrogen to produce radioactive carbon-14. Radioactive C-14 enters all living tissues through carbon dioxide, which is first absorbed by plants. As long as a plant or animal is alive, C-14 is maintained in the living organism at a constant level. Once the organism dies, C-14 decays according to the equation A=A0e^-0.000124t where A is the amount present after t years and A0 is the amount present at the time of death. If 500 milligrams of C-14 (that is A0=500) are present in a sample from a skull at the time of death, how many milligrams will be present in the sample in 15,000 45000.00 60000 years. From your results, what can you conclude about using C-14 dating on bones from animals believed to exist 200,000,000 years ago? To be honest I am not even sure how to approach this question. Any help will be greatly appreciated. Thanks everyone.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! A=A0e^-0.000124t where A is the amount present after t years and A0 is the amount present at the time of death. If 500 milligrams of C-14 (that is A0=500) are present in a sample from a skull at the time of death, how many milligrams will be present in the sample in 15,000 45000.00 60000 years. From your results, what can you conclude about using C-14 dating on bones from animals believed to exist 200,000,000 years ago?
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A(t) = A(0)e^-0.000124t
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I don't have time to do all the calculator work on this.
Find A(15000) = 500e^(-0.000124*15000)
= 500*e^(-1.86)
= 500*0.1557
= 77.8363
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Find A(45000)
Find A(60000)
Find A(200,000,000)
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Cheers,
Stan H.
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