SOLUTION: If 40mg of a radioactive substance dcays to 5mg in 12min, find the half-life, in minutes of the substance.
The halflife formula is
N = No (1/2) ^t/h
so i think that the for
Algebra.Com
Question 80635: If 40mg of a radioactive substance dcays to 5mg in 12min, find the half-life, in minutes of the substance.
The halflife formula is
N = No (1/2) ^t/h
so i think that the formula goes to
5 = 40 (1/2) ^ 5/h but im not sure if thats right and i can't figure out how to solve
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
If 40mg of a radioactive substance dcays to 5mg in 12min, find the half-life, in minutes of the substance.
------------
Decay formula: A(t) = Ao(x)^t
5 = 40(x)^12
1/8 =x^12
x=0.841
--------
EQUATION:
A(t) = Ao (0.841)^t
--------
Now find the half-life:
(1/2)Ao = Ao(0.841)^t
(1/2)=(0.841)^t
t=ln(1/2) / ln0.841 = 4 minutes
----------
The half-life is 4 minutes.
==========
Cheers,
Stan H.
RELATED QUESTIONS
If 40 mg of a radioactive substance decays to 5mg in 12 minutes, find the half-life, in... (answered by ankor@dixie-net.com)
If 40 mg of a radioactive substance decays to 5 mg in 12 minutes, find the half life of... (answered by josgarithmetic)
A radioactive substance decays from 20 pounds to 19.9 pounds in 25 years. approximate the (answered by Fombitz)
Find the half-life of a radioactive substance that is reduced by 30% in 20... (answered by Madgamer107)
Find the half life of a radioactive substance that decays by 20% in 10... (answered by stanbon)
Find the half-life of a radioactive substance that decays by 2% in 9... (answered by ankor@dixie-net.com)
What is the half-life of a radioactive substance if 2.4g decays to .80g in 40... (answered by Fombitz)
A radioactive substance has a halflife of 120 years. If 200mg of substance was present,... (answered by ewatrrr)
A radioactive substance has a halflife of 120 years. If 200mg of substance was present,... (answered by josgarithmetic)