Radioactive Decay Graph in y=mx+c form

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The discussion centers on transforming the radioactive decay equation into y=mx+c form for graphing purposes. The equation provided relates the radioactivity of lead in marine sediments to sediment depth, using parameters such as activity at depth and decay constant. The user attempts to manipulate the equation by taking the natural logarithm of both sides, ultimately expressing it in linear form. Another participant confirms the transformation is correct, noting that the slope is negative and defined by the decay constant divided by the sediment accumulation rate. The final graph will plot Ln AL against sediment depth L, with specific values for slope and intercept.
Rockerjabroni
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Homework Statement



This is an equation relating radioactivity of lead in marine core sediments in comparison with the depth of the sediment.

The equation is AL=A0exponential - λL/s

Where AL = activity at depth L (Bqkg-1)
Where A0 = activity at depth 0 cm (Bqkg-1)
λ = decay constant 0.031 yr-1
L= sediment depth (cm)
s= sediment accumulation rate (cmyr-1)

I need to make this into y=mx+C form


Homework Equations



As above.

The Attempt at a Solution



Well Ln both sides gives me

Ln AL = Ln (A0exponential - λL/s)

Ln AL = (Ln A0) + (Ln*exponential - λL/s) (which cancels)

Ln AL = (Ln A0) - λL/s

Ln AL = y
Ln (A0) = c
L= x
1/s = m

Is that correct? The graph has to be Ln AL against L but I wasn't sure about m and c. Thanks :)
 
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Hello Rockerjabroni your equation is correct.If you now compare this to y=mx+c you should see that the graph has a negative slope of gradient lambda/s and intercept lnAzero.
 
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