16 grams of radioactive material decays in 10 years. How long will it take to decay to 1 gram?

• every radio active element decays to half of its weight evry time.. whenever bombarded.
  so, it decays into 16-> 8-> 4->2->1
  Totally it takes 40 years to decay to 1gram.
• 10 years agoHelpfull: Yes(15) No(2)
• 16gm in 10 yr
  .
  . . 1gm in 10/16=.625
• 10 years agoHelpfull: Yes(7) No(7)
• i think 10 years
• 10 years agoHelpfull: Yes(3) No(6)
• 16 gm reduced to 8gm in 10yrs
  so 8 gm get decayed
  for decaying 1 gm it takes 10/8 yrs
  for decaying 8 gm it takes 10/8*8
  
  remaining 8 gm
  need to decay 7 to get 1 gm remaining
  for decaying 7 it takes
  10/8*8*7
  =10*7
  =70 years
• 10 years agoHelpfull: Yes(3) No(2)
• 16 gm reduced to 8gm in 10yrs. So 8 gm get decayed.
  For decaying 1 gm it takes 10/8 years. For decaying 8 gm it takes 10/8*8
  Remaining 8 gm need to decay 7 to get 1 gm remaining.
  For decaying 7 gm it will take
  10/8*8*7 = 10*7 = 70 years
• 9 years agoHelpfull: Yes(1) No(1)
• decay of radioactive material is given by n(t)=n(t0)*exp^(-At)... after 10 years of decay the substance will not reduce to exactly 0 (it will tend to 0). i considered it to be .001 gm then calculated A by taking ln of both the sides and then solved problem for 1 gm it comes out to be 7.135 years.
  
• 9 years agoHelpfull: Yes(1) No(0)