Posted by james on Tuesday, January 22, 2013 at 10:15pm.
For half-life question, a good equation to use is
amount = starting value (1/2)^(t/k) where k is the half-life
so :
.35 = 1(1/2)^(t/2000) , t in years
.35 = (.5)^(t/2000
log .35 = log ( (.5)^(t/2000)
log .35 = (t/2000) log .5
t/2000 = log .35/log .5
t = 2000( log .35/log .5) = 3029.14
it would take appr 3029 years
Related Questions
calculus - The rate at which an amount of a radioactive substance decays is ...
Math - In 10 years, 25% of a radioactive substance decays. What is its half-life...
Algebra - In 10 years, 25% of a radioactive substance decays. What is its half-...
Chemistry - Which radioactive sample would contain the greatest remaining mass ...
Science - A material has 32 atoms in all; 24 decayed and the rest undecayed. If ...
Science - If a 20 gram sample of a radioactive substance has a half-life of 6000...
Calculus - A certain radioactive material decays exponetially. The percent, P, ...
Science - Radioactive substance decays so that after t years, the amount ...
Calc - A sample of a radioactive substance decayed to 93.5% of its original ...
Pre Calculus - Exponential growth and decay find the half life of a radioactive ...
For Further Reading
