Decay constant Definition and 26 Threads

A quantity is subject to exponential decay if it decreases at a rate proportional to its current value. Symbolically, this process can be expressed by the following differential equation, where N is the quantity and λ (lambda) is a positive rate called the exponential decay constant:







d
N


d
t



=

λ
N
.


{\displaystyle {\frac {dN}{dt}}=-\lambda N.}
The solution to this equation (see derivation below) is:




N
(
t
)
=

N

0



e


λ
t


,


{\displaystyle N(t)=N_{0}e^{-\lambda t},}
where N(t) is the quantity at time t, N0 = N(0) is the initial quantity, that is, the quantity at time t = 0, and the constant λ is called the decay constant, disintegration constant, rate constant, or transformation constant.

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  1. E

    B What is meant by decay constant?

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  2. A

    B How are activity and decay constant different?

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  3. WhiteWolf98

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  4. A

    I Dimensions of the pion decay constant

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  6. S

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  7. Kingyou123

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  8. CivilSigma

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  9. S

    How Does the Decay Constant Influence Water Flow in Exponential Decay Models?

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  10. P

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  11. G

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  12. N

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  13. F

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  14. F

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  15. E

    What is meant by 'decay constant'?

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  16. S

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  17. S

    Nuclear physics - decay constant

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  18. R

    Radioactive Decay: Mean Life Time & Decay Constant

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  19. R

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  20. I

    Need help understanding Half life, decay constant & activity equations

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  21. N

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  22. S

    How to Determine the Decay Constant of a Radioactive Substance?

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  23. M

    Using differential equations to determine the decay constant for carbon-14

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  24. M

    Derivations of the Decay Constant Equation.

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  25. E

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