Question

CALCULUS HELP

In the early 1960s, radioactive strontium-90 was released during atmospheric testing of nuclear weapons and got into the bones of people alive at the time. If the half-life of strontium-90 is 29 years, the fraction of the strontium-90 absorbed in 1960 remaining in peoples bones in 1990 is ________________%

Answer 1

Wrong section, please make sure you look before you post.

Answer 2

if you think this isnt math, youve never taken calculus obviously,

Answer 3

so please read before you post.

Answer 4

50%

Answer 5

see half life is 29 years .. and there are 29 years till 1990 starts..

Answer 6

any chance you can elaborate on that answer? i sort of need to learn the material

Answer 7

ahh so you didnt atually use the formula

Answer 8

50% is incorrect

Answer 9

i just used half life .. half life means when nuclear substance reduces to half

Answer 10

yes exactly

Answer 11

There is a formula that will give the amount left based on the amount of time gone by and the half-life of the element in question and it is calculus based so that might be what the user is looking for

Answer 12

it may be between 49-50 %

I guess my answer is correct. (50%)

Answer 13

I agree

Answer 14

no 50% is incorret

Answer 15

There is an exact answer for the percent REMAINING IN PEOPLE'S BONES which is not %50

Answer 16

john do you know how to do this? if so can you please help me

Answer 17

I agree not correct

Answer 18

see.. it has asked the amount remaining in people's bone in 1990. that means it is calculating at the start of the year 1990. it means 29 years has passed .. if 29 years has passed .. that means .. it has gone through half life

Answer 19

tech have you ever taken calculus?

Answer 20

man are you kidding me ??

Answer 21

I have taken Differential equations which limits me on helping you but if you find the formula they want you to use I might be able to assist better

Answer 22

do you understand what i am talking about .. half life and pellet

Answer 23

and it was absorbed in 1960, they are asking how much is remaining in bones in 1990, it doesnt start calculating in 1990

Answer 24

30 years have gone by ... 1990 - 1960 = 30
Half life is 29 years.
\[29 \neq 30\]

Answer 25

i probably have it written down somewhere, just a second

Answer 26

@nsellers23 do you know what half life is ..

Answer 27

http://en.wikipedia.org/wiki/Half-life

Answer 28

P = a^t, for 0 < a < 1 i believe this is the equation

Answer 29

well techworm, if you know what/how to do this, then why does it say your answer is incorrect

Answer 30

@Johnbc : 30 years havent gone by .. 30th year has just started at 1990.. so the years passed by is 29 ..

Answer 31

look at the picture

Answer 32

@nsellers23 : cant he/she be incorrect.. just consult your physics teacher ..

Answer 33

this isnt physics, this is calculus. it may be different?

Answer 34

try 50.0 or 50.00 .. i dont remember which tenth place is

Answer 35

50.0 would be tenths place and says incorret still

Answer 36

@nsellers23 : leave it man .. leave it .. its worthless to discuss with you

Answer 37

ha how so.. im just saying the answer youve provided me with is incorrect

Answer 38

talk your calculus teacher.. if it isnt physics question ..

Answer 39

try (0.5)^(30/29)

Answer 40

ok thank you tech, no one is forcing you to stay here. thanks for your help.

Answer 41

thank you phi! that is correct

Answer 42

Thanks to anyone who helped me.