Question
You have 480 grams of a radioactive kind of tin. If its half-life is 10 days, how much will be left after 30 days?
Answers
Bosnian
After 10 days you have half left
After 20 days that's half of the half again = a quarter
After 30 days that's half of a quarter = an eighth
480 / 8 = 60 grams
After 20 days that's half of the half again = a quarter
After 30 days that's half of a quarter = an eighth
480 / 8 = 60 grams
Bosnian
Equation :
N( t ) = N( 0 ) * ( 1 / 2 ) ^ [ t / t( 1 / 2) ]
In this case :
N ( 30 ) = 480 * ( 1 / 2 ) ^ ( 30 / 10 )
N ( 30 ) = 480 * ( 1 / 2 ) ^ 3
N ( 30 ) = 480 * 1 / 8 = 60 grams
N( t ) = N( 0 ) * ( 1 / 2 ) ^ [ t / t( 1 / 2) ]
In this case :
N ( 30 ) = 480 * ( 1 / 2 ) ^ ( 30 / 10 )
N ( 30 ) = 480 * ( 1 / 2 ) ^ 3
N ( 30 ) = 480 * 1 / 8 = 60 grams
Bosnian
Also you can in google type:
half-life equation
and click : en.wikipedia
half-life equation
and click : en.wikipedia
Anonymous
Suppose that a certain radioactive substance has a half-life of 20 years. If there are presently 2400 milligrams of the substance, how much, to the nearest milligram, will remain after 70 years?