Go Back   Physics Help Forum > College/University Physics Help > Nuclear and Particle Physics

Nuclear and Particle Physics Nuclear and Particle Physics Help Forum

Reply
 
LinkBack Thread Tools Display Modes
Old Nov 4th 2009, 12:31 PM   #1
Junior Member
 
Join Date: Oct 2009
Posts: 5
I am rigth? please help!

question:

Some soil contains 3ppb(parts per billion by weight) U-238. Calculate the specific activity of the soil.


t(1/2)=half life = 4.468*10^9(y)
mass M=238

the activity of 1g U-238:

A= (6.02*10^23)*ln(2)/[t(1/2)]*M
= (6.02*10^23)*0.693/(4.468*10^9)*238
= 12445Bq/g

3ppb=3/10^9(g)

Finally, A = [3/10^9(g)]* (12445Bq/g)=3.6735/10^5Bq/g=9.93/10^13Ci/g

Is it right? thanks for help!!!
newer is offline   Reply With Quote
Old Nov 4th 2009, 10:23 PM   #2
Senior Member
 
Join Date: Sep 2009
Location: india
Posts: 409
correct me if i am wrong? dont i have to convert half life given in years to seconds by multiplying 365*24*60*60??then only the unit comes in bequerel .

Last edited by r.samanta; Nov 4th 2009 at 10:26 PM.
r.samanta is offline   Reply With Quote
Reply

  Physics Help Forum > College/University Physics Help > Nuclear and Particle Physics

Tags
rigth



Thread Tools
Display Modes



Facebook Twitter Google+ RSS Feed