# Help with a logarithm please watch

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1. I have been given a question on radioactive decay for uni and I have no clue how to do it! Any help would be greatly appreciated.In the equation for radioactive decay, Nt/N0 = e^-kt where N0 = starting amount of radio activity (at t =0) , Nt = radioactivity at time t, and k is a constant to each particular radioactive isotope.A radio active isotope decays to 50% of it initial radioactivity in 37.35 hours. Calculate the value of k for this isotope. I am really stuck and can’t seem to work it out any help is hugely appreciated
2. (Original post by Rhockeymorley317)
I have been given a question on radioactive decay for uni and I have no clue how to do it! Any help would be greatly appreciated.In the equation for radioactive decay, Nt/N0 = e^-kt where N0 = starting amount of radio activity (at t =0) , Nt = radioactivity at time t, and k is a constant to each particular radioactive isotope.A radio active isotope decays to 50% of it initial radioactivity in 37.35 hours. Calculate the value of k for this isotope. I am really stuck and can’t seem to work it out any help is hugely appreciated
I'm assuming is taken in hours, so . We know that is half , so how can we set up an equation to be solved?
3. why are you stuck , doesn't what you said in the title pretty much solve it ? isn't it easy if you use ln ?
4. I have to find k, I don’t understand how to solve the equation to find k?
5. (Original post by Rhockeymorley317)
I have been given a question on radioactive decay for uni and I have no clue how to do it! Any help would be greatly appreciated.In the equation for radioactive decay, Nt/N0 = e^-kt where N0 = starting amount of radio activity (at t =0) , Nt = radioactivity at time t, and k is a constant to each particular radioactive isotope.A radio active isotope decays to 50% of it initial radioactivity in 37.35 hours. Calculate the value of k for this isotope. I am really stuck and can’t seem to work it out any help is hugely appreciated
u know the half life so u can use the half life equation to find the constant value.
half life=ln2/k
that's what I would do-if the question is more than two marks then that's not the way
6. isn't this correct ?
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7. (Original post by AndreiMiron)
x
Best not to post full solutions We prefer to give the OP hints towards the correct solution, with full solutions you run the risk of the OP copying the answer without understanding how it was reached. You might be interested in checking out the posting guidelines
8. (Original post by _gcx)
Best not to post full solutions We prefer to give the OP hints towards the correct solution, with full solutions you run the risk of the OP copying the answer without understanding how it was reached. You might be interested in checking out the posting guidelines
Didn't know about that I am new on this forum
9. (Original post by AndreiMiron)
Didn't know about that I am new on this forum
No worries

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