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Ml Dermody
Ml Dermody asked in Science & MathematicsPhysics · 2 years ago

The no. of radioactive nuclei in particular sample decreases over 14 d to one-sixteenth original no.What is half-life?

2 Answers

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  • ?
    Lv 7
    2 years ago
    Favorite Answer

    Use the formula.

    n=n0 exp -at, n/no = exp (- a14)

    n1/n0 = 1/2 = exp (-a d)

    Divide one by the other

    n/n0=1/16

    Take log on both sides

    ln(1/16)/ln(1/2) =14 /d=-2.77/-.69=4.

    d=14/4=3.5 days will be the half life.

  • billrussell42
    Lv 7
    2 years ago

    1/16 means 4 half lives

    1 ➔ 1/2 ➔ 1/4 ➔ 1/8 ➔ 1/16

    14/4 = 7/2 days

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