Hi guys(adsbygoogle = window.adsbygoogle || []).push({});

i'm having much difficulties in understanding the relations between half life, decay constant and activity.

I'll explain what i known here.

[tex]T^{\frac{1}{2}}[/tex] is the half life which is the time to reduce the nuclides by half.

[tex]\lambda[/tex] is the decay constant which can be solved from

[tex]\lambda[/tex] = 0.693/ [tex]T^{\frac{1}{2}}[/tex]. Am i correct? Where do 0.693 come from?

The decay/sec can be find out using [tex]A = -\frac{dN}{dt} = \lambda N[/tex] if the half life and N is known.

I want to clarify N is in grams? So like 10g of C14 would be the No?

I don't really understand this equation:

[tex]

\frac{dN}{dt} = -\lambda N

[/tex]

i know why it is negative [tex] \lambda N [/tex] as it's decreasing exponentially but what do the d and t stands for? Does the t stands for the half life? What is the use of the equation?

Thanks a bunch!

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# Need help understanding Half life, decay constant & activity equations

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