The Student Room Group
Uni students - Complete our survey >>
Uni students - Complete our survey >>
Uni students - Complete our survey >>

Nuclei Decay. Help

The Half life of a waste material is 6 months.

Show that the activity will decrease about 1000 in 5 years.
(edited 6 years ago)
Original post by joyoustele
The Half life of a waste material is 6 months.

Show that the activity will decrease about 10000 in 5 years.



Are you sure 10,000 is the correct answer?
Reply 2
Avatar for joyoustele
joyoustele
OP
19
Original post by uberteknik
Are you sure 10,000 is the correct answer?


sorry, it's 1,000
Original post by joyoustele
sorry, it's 1,000


OK.

You can use the relationship:

Nt=Nt0(e−tτ)N_{t} = N_{t_{0}}(e^{\frac{-t}{\tau}})

and

t12=τln(2)t_{\frac{1}{2}} = \tau ln(2)

where

t=total decay timet = \textrm{total decay time}

t12=half lifet_{\frac{1}{2}} = \textrm{half life}

τ=decay time constant\tau = \textrm{decay time constant}
Reply 4
Avatar for joyoustele
joyoustele
OP
19
Original post by uberteknik
OK.

You can use the relationship:

Nt=Nt0(e−tτ)N_{t} = N_{t_{0}}(e^{\frac{-t}{\tau}})

and

t12=τln(2)t_{\frac{1}{2}} = \tau ln(2)

where

t=total decay timet = \textrm{total decay time}

t12=half lifet_{\frac{1}{2}} = \textrm{half life}

τ=decay time constant\tau = \textrm{decay time constant}


Thanks, i managed to do it
Original post by joyoustele
Thanks, i managed to do it


You don't need to convert to seconds since it's the ratio of the times that are needed, just keep the time units the same. i.e. 6 months and 60 months (5 years).
Reply 6
Avatar for joyoustele
joyoustele
OP
19
Original post by uberteknik
You don't need to convert to seconds since it's the ratio of the times that are needed, just keep the time units the same. i.e. 6 months and 60 months (5 years).


oh. Okay. Thank you very much

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you