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# AQA Physics Chapter 2: Conservation Laws

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1. I'm really stuck on this question, I know how to show that the collision obeys three conservation laws however not energy and momentum. Any help would be great.
"The equation represents the collision of a neutral kaon with a proton, resulting in the production of a neutron and a positive pion.
K° + p n + π+
(a) Show that this collision obeys three conservation laws in addition to energy and momentum."
2. The conservation laws that you need to show are satisfied are the conservation of charge, baryon number and lepton number. Do you know the charge, baryon number and lepton number of all of the particles taking part in the interaction?
3. (Original post by Pangol)
The conservation laws that you need to show are satisfied are the conservation of charge, baryon number and lepton number. Do you know the charge, baryon number and lepton number of all of the particles taking part in the interaction?
Yes, charge and baryon no.=1 on each side and lepton no.=0, however i do not know how to show that it obeys conservation of energy and momentum.
Charge:
p=1
k°=0
n=0
π+ =1

Baryon no.:
p=1
k°=0
n=1
π+ =0

Lepton no.:
p=0
k°=0
n=0
π+ =0
however i do not know how to show that it obeys conservation of energy and momentum.
Ah! If that's your problem, well, it isn't a problem. You don't have the information that you need to show that it satisfies conservation of energy and momentum. The question is phrased in this way so that you know that energy and momentum are conservation laws that you don't have to check - they are testing you on (a) whether or not you know what the laws you need to check are, and (b) if you can do it (as you have just shown that you can).

You know that energy and momentum are conserved, becasue they always are, but you don't have the information you would need to verify this. You just have to verify the other three.
5. (Original post by Pangol)
Ah! If that's your problem, well, it isn't a problem. You don't have the information that you need to show that it satisfies conservation of energy and momentum. The question is phrased in this way so that you know that energy and momentum are conservation laws that you don't have to check - they are testing you on (a) whether or not you know what the laws you need to check are, and (b) if you can do it (as you have just shown that you can).

You know that energy and momentum are conserved, becasue they always are, but you don't have the information you would need to verify this. You just have to verify the other three.
Thank you, I was a bit puzzled as to why it would want me to find it as none of the other question mentioned it

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