Simple decay question

Smythe

In the attachment the question in given at the top, then the correct solution under this in green, then my attempt below this in red.

I'm getting the same solution for N-zero but as a negative number. So I'm wondering what is wrong? Perhaps it's simply a matter of taking the magnitude?

Thanks for any help!

Morbert

Smythe wrote: »

In the attachment the question in given at the top, then the correct solution under this in green, then my attempt below this in red.

I'm getting the same solution for N-zero but as a negative number. So I'm wondering what is wrong? Perhaps it's simply a matter of taking the magnitude?

Thanks for any help!

dN/dt is negative (I.e. N gets smaller or "decays" with increasing time t). You've written it down as a positive number.

Smythe

Morbert wrote: »

dN/dt is negative (I.e. N gets smaller or "decays" with increasing time t). You've written it down as a positive number.

Thanks Morbert.

So in the first line of my solution (in red) do you mean I should have

-dN/dt = - λ N0 e^-λt

Morbert

Smythe wrote: »

Thanks Morbert.

So in the first line of my solution (in red) do you mean I should have

-dN/dt = - λ N0 e^-λt

You should have

dN/dt = - λ N0 e^-λt

where dN/dt = -600×106s-1

Smythe

Thanks Morbert!