example 7
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example 7. Carbon-14 Dating. Chapter 5.1. During the life of an organism, the ratio of carbon-14 (C-14) to carbon-12 (C-12) atoms - PowerPoint PPT PresentationTRANSCRIPT
example 7 Carbon-14 Dating
Chapter 5.1
During the life of an organism, the ratio of carbon-14 (C-14) to carbon-12 (C-12) atomsremains about the same. When the organism dies, the ratio of C-14 atoms within its carcass begins to gradually decrease, but the C-12 does not, so they can be measured to see how many C-14 atoms were present at death. Comparing the number of C-14 atoms when it is discovered with the number at death can be used to find how long ago the organism lived. The ratio of the present amount of C-14 to the original amount t years ago is given by
This gives a function
that gives the amount remaining after t years.(Source: Thomas Jefferson National Accelerator Facility, http://www.jlab.org/)
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097
0
tye
y
0.000120970( ) ty f t y e
2009 PBLPathways
2009 PBLPathways
During the life of an organism, the ratio of carbon-14 (C-14) to carbon-12 (C-12) atomsremains about the same. When the organism dies, the ratio of C-14 atoms within its carcass begins to gradually decrease, but the C-12 does not, so they can be measured to see how many C-14 atoms were present at death. Comparing the number of C-14 atoms when it is discovered with the number at death can be used to find how long ago the organism lived. The ratio of the present amount of C-14 to the original amount t years ago is given by
This gives a function
that gives the amount remaining after t years.(Source: Thomas Jefferson National Accelerator Facility, http://www.jlab.org/)
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097
0
tye
y
0.000120970( ) ty f t y e
2009 PBLPathways
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
0.000120970( ) tf t y e
0.00012097 2000
0.24194
(2000) 100
100
78.51
f e
e
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097 45000
0.5443650
0
(4500)
0.58
f y e
y e
y
Time in years
Original amountAmount remaining
2009 PBLPathways
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
0.00012097 2000
0.24194
(2000) 100
100
78.51
f e
e
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097 45000
0.5443650
0
(4500)
0.58
f y e
y e
y
Time in years
Original amountAmount remaining
0.000120970( ) tf t y e
2009 PBLPathways
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
0.00012097 2000
0.24194
(2000) 100
100
78.51
f e
e
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097 45000
0.5443650
0
(4500)
0.58
f y e
y e
y
Time in years
Original amountAmount remaining
0.000120970( ) tf t y e
2009 PBLPathways
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
0.00012097 2000
0.24194
(2000) 100
100
78.51
f e
e
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097 45000
0.5443650
0
(4500)
0.58
f y e
y e
y
Time in years
Original amountAmount remaining
0.000120970( ) tf t y e
2009 PBLPathways
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
0.00012097 2000
0.24194
(2000) 100
100
78.51
f e
e
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097 45000
0.5443650
0
(4500)
0.58
f y e
y e
y
Time in years
Original amountAmount remaining
0.000120970( ) tf t y e
2009 PBLPathways
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
0.00012097 2000
0.24194
(2000) 100
100
78.51
f e
e
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097 45000
0.5443650
0
(4500)
0.58
f y e
y e
y
Time in years
Original amountAmount remaining
0.000120970( ) tf t y e
2009 PBLPathways
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
0.00012097 2000
0.24194
(2000) 100
100
78.51
f e
e
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097 45000
0.5443650
0
(4500)
0.58
f y e
y e
y
Time in years
Original amountAmount remaining
0.000120970( ) tf t y e
2009 PBLPathways
a. If the original amount of carbon-14 present in an artifact is 100 grams, how much remains after 2000 years?
0.00012097 2000
0.24194
(2000) 100
100
78.51
f e
e
b. What percent of the original amount of carbon-14 remains after 4500 years?
0.00012097 45000
0.5443650
0
(4500)
0.58
f y e
y e
y
Time in years
Original amountAmount remaining
0.000120970( ) tf t y e