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If a 125 gms of radioactive element has a half life of 60 min how many half lives will it go through to become 3.90625 gms

User Rauschen
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1 Answer

4 votes

Answer:

  • 5

Step-by-step explanation:

Let the number of half lives be x

Solve this equation to find the value of x:

  • 125*(1/2)ˣ = 3.90625
  • (0.5)ˣ = 3.90625 / 125
  • (0.5)ˣ = 0.03125
  • log (0.5)ˣ = log 0.03125
  • x = log 0.03125 / log 0.5
  • x = 5

User Richard Logwood
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