The half-life of a certain radioactive substance is 48 hours. There are 20 grams present initially.
a) Express the amount of substance remaining as a function of time t.
b) When will there be 13 grams remaining in hours?
I know that my formula for (a) would look something like this: y= 20(1/2)^(?). I'm stumped on the exponential part.
An explanation would be great! Thank you!
a) Express the amount of substance remaining as a function of time t.
b) When will there be 13 grams remaining in hours?
I know that my formula for (a) would look something like this: y= 20(1/2)^(?). I'm stumped on the exponential part.
An explanation would be great! Thank you!
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a. y = 20*0.5^(t/48)
b. 13 = 20*0.5^(t/48) , 0.5^(t/48) = 0.65 , t/48*log 0.5 = log 0.65 ,
t = 48*log 0.65 /log 0.5 = 29.83 hrs <-------
b. 13 = 20*0.5^(t/48) , 0.5^(t/48) = 0.65 , t/48*log 0.5 = log 0.65 ,
t = 48*log 0.65 /log 0.5 = 29.83 hrs <-------