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Physics IGCSE question

So one of the questions included "define half life" (2 marks)
I put "the time it takes for half the radioactivity of the radioactive material to half"... would you say that makes sense and would be able to gain the 2 marks?

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No, the answer is:

The time taken for the amount of radioactive decay to decrease by half

OR

The time taken for half of the radioactive decay present to decay.

With respect, you seem to have waffled, and your definition could be interpreted to mean HALF of the half life!

Look in the cgp guide :d

You doing edexcel?
Reply 2
Avatar for Neymar27
Neymar27
6
Original post by Damien_Dalgaard
No, the answer is:

The time taken for the amount of radioactive decay to decrease by half

OR

The time taken for half of the radioactive decay present to decay.

With respect, you seem to have waffled, and your definition could be interpreted to mean HALF of the half life!

Look in the cgp guide :d

You doing edexcel?


What about 'time taken for half the mass of a radioactive isotope to decay'?
Original post by Neymar27
What about 'time taken for half the mass of a radioactive isotope to decay'?


I quote from my revision guide:

"The half - life t(1/2) of an isotope is the average time taken for half of the active nuclei to decay".

If you are not satisisfied look at a past exam question in your exam board and look at the mark scheme answer, you will be sorted then :yep:

Its not mass though is it? I thought it was radioactive matter smh
Reply 4
Avatar for Neymar27
Neymar27
6
Original post by Damien_Dalgaard
I quote from my revision guide:

"The half - life t(1/2) of an isotope is the average time taken for half of the active nuclei to decay".

If you are not satisisfied look at a past exam question in your exam board and look at the mark scheme answer, you will be sorted then :yep:

Its not mass though is it? I thought it was radioactive matter smh


Must have misread it from the textbook then I guess,,, hopefully one mark anyway for putting a few key words in
Original post by Damien_Dalgaard
No, the answer is:

The time taken for the amount of radioactive decay to decrease by half

OR

The time taken for half of the radioactive decay present to decay.

With respect, you seem to have waffled, and your definition could be interpreted to mean HALF of the half life!

Look in the cgp guide :d

You doing edexcel?


Yep I'm doing edexcel :\
Wait, would this definition work "the time it takes for the radioactivity of the radioactive material to half"?
Original post by simply_a_ Δ
Yep I'm doing edexcel :\
Wait, would this definition work "the time it takes for the radioactivity of the radioactive material to half"?



Yes I would agree with that.
Reply 7
Avatar for Neymar27
Neymar27
6
Original post by Damien_Dalgaard
Yes I would agree with that.


I found a definition though for it being 'mass' in the Pearson textbook
Original post by Neymar27
I found a definition though for it being 'mass' in the Pearson textbook


I am doing Physics A2, so maybe the definition is different. Look at a past exam question for your exam board and see what the mark scheme says the definition is.
Reply 9
Avatar for Neymar27
Neymar27
6
Original post by Damien_Dalgaard
I am doing Physics A2, so maybe the definition is different. Look at a past exam question for your exam board and see what the mark scheme says the definition is.

I'll just leave it lol, incase it's wrong and I then think I've gone down even more lol
Original post by Neymar27
I'll just leave it lol, incase it's wrong and I then think I've gone down even more lol


gl
Original post by Damien_Dalgaard
Yes I would agree with that.


Thank you for the reply :P as you can tell, I still haven't fully grasped the definition of half life and I'm doing paper 2 IGCSE in a couple of weeks xD
Thanks, and im doing IGCSE Edexcel btw
Original post by Damien_Dalgaard
gl
Original post by simply_a_ Δ
Thank you for the reply :P as you can tell, I still haven't fully grasped the definition of half life and I'm doing paper 2 IGCSE in a couple of weeks xD


dw I self taught it and as long as you are confident with the material and do all the past papers you'll go far!

The good thing about half life is that the "half" in its name is relevant to the definition, just

Original post by Neymar27
Thanks, and im doing IGCSE Edexcel btw


xD, I did that :P
Original post by Neymar27
I found a definition though for it being 'mass' in the Pearson textbook


yes it did say mass my school uses the pearson book too
Original post by simply_a_ Δ
So one of the questions included "define half life" (2 marks)I put "the time it takes for half the radioactivity of the radioactive material to half"... would you say that makes sense and would be able to gain the 2 marks?


For igcse edexcel, the mark scheme from past papers gave these definitions:

The time taken (1) for the activity of the radioactive sample to half (1)

The time taken (1) for half of the nuclei / atoms / isotopes to decay (1)

:smile: Good luck for the exam btw
Original post by turn-to-page394
For igcse edexcel, the mark scheme from past papers gave these definitions:

The time taken (1) for the activity of the radioactive sample to half (1)

The time taken (1) for half of the nuclei / atoms / isotopes to decay (1)

:smile: Good luck for the exam btw


Oh wow! Thank you for finding the time to look through the markscheme :smile:
Original post by simply_a_ Δ
Oh wow! Thank you for finding the time to look through the markscheme :smile:


Oh no, it's fine - I'm taking the exam too and remembered a question like that from past papers. :smile:
Original post by Damien_Dalgaard
No, the answer is:

The time taken for the amount of radioactive decay to decrease by half

OR

The time taken for half of the radioactive decay present to decay.

With respect, you seem to have waffled, and your definition could be interpreted to mean HALF of the half life!

Look in the cgp guide :d

You doing edexcel?


the time taken for half the amount of radioactive atom to decay
Original post by Zakariyam10
the time taken for half the amount of radioactive atom to decay


This is the same as what I said.

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