plutonium-239 is a by-product of nuclear reactors. it has a half-life of about 24000 yrs. for what period of time does a quantity of 239Pu have to be stored until it is considered safe to handle?

Question

anonymous · Answer

@Australopithecus    @experimentX

rane · Answer

online han kya ye?

anonymous · Answer

@experimentX  hai ...

experimentx · Answer

what is the initial quantity of plutonium? also how much radiation can be considered as safe?

rane · Answer

this all the info i'm given

experimentx · Answer

convert that half life into e^(-lambda t) from http://en.wikipedia.org/wiki/Half-life#Formulas_for_half-life_in_exponential_decay for that you need original amount of material ... say 1kg = 6.023*10^23*10^3/239 find dN/dt ... I do not know what level of radiation can be called safe. Google for it ... dN/dt gives your radiation count per sec.

experimentx · Answer

put dN/dt <= safety level and solve for 't'

experimentx · Answer

also check your question again
 does a quantity ?? of 239Pu
                        ^^ what quantity ??

rane · Answer

i did checked it again bt this all wht i'm given

experimentx · Answer

probably some typo in question ... initial amount of material has to be given. 
if initial amount is very large, it will produce radiation for longer time if it is less then it will produce radiation for short time.

experimentx · Answer

or possibly I am not understanding the question.

rane · Answer

ok thanks anyway

experimentx · Answer

http://physics.stackexchange.com/questions/8264/are-these-radioactive-particle-matter-and-air-emmissions-dangerous-2000km-from the safely level is 100-100 Bec/kg http://en.wikipedia.org/wiki/Becquerel#Calculation_of_radioactivity put that equation < 100 Bec ... for that you need 'm' best of luck

rane · Answer

thank u

anonymous · Answer

did you get your answer.. @RANE

rane · Answer

nahi yar

anonymous · Answer

hmmm

anonymous · Answer

hhmmmm k