Plants incorporate carbon as long they live. Once a plant dies, it takes how many years for 99.9% of the carbon-14 to decay (half-life of C-14 is 5730 years)?
+37146 We are looking for the time when .1% of the original is left ..... or .001 x original
1/2^n = .001 Log both side
Log(1/2^n) = Log(.001)
n Log1/2 = -3
n = number of half lives = -3/(log(1/2) = 9.965784284 half lives
9.965784284 (5730) = 57103.94394732 years
+37146 We are looking for the time when .1% of the original is left ..... or .001 x original
1/2^n = .001 Log both side
Log(1/2^n) = Log(.001)
n Log1/2 = -3
n = number of half lives = -3/(log(1/2) = 9.965784284 half lives
9.965784284 (5730) = 57103.94394732 years
Plants incorporate carbon as long they live. Once a plant dies, it takes how many years for 99.9% of the carbon-14 to decay (half-life of C-14 is 5730 years)?
.001=2^-t
0.001 = 2^(-t)
0.001 = 1/1000:
1/1000 = 2^(-t)
1/1000 = 2^(-t) is equivalent to 2^(-t) = 1/1000:
2^(-t) = 1/1000
Take reciporicals of both sides:
2^t = 1000
Take the logarithm base 2 of both sides:
Answer: | t = (log(1000))/(log(2))=9.965 halve lives, or 9.965 x 5,730=57,099.45 years
