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a level physics-particles and radiation help

in the revision textbook, it says, therefore, the minimum energy of each photon HFmin is given by equating the energy of the two photons 2FHmin to the rest energy of the particle and the antiparticle 2hfmin=E0 I don't get what that means

then it says the minimum energy of a photon=2 x 0.511 MeV =1.022 i get that but then it says it also = 1.64 x 10^-13 J where did they get that from? can somebody help please :biggrin:
Hint: what is the relationship between MeV and J?
Original post by artful_lounger
Hint: what is the relationship between MeV and J?

yh i get it now 1 mev =1.60 x 10^-13 J :biggrin: thank you and also is the rest energy of a proton 0.938 or 938 becuase for an electron its 0.511
Original post by imgoonafailife
yh i get it now 1 mev =1.60 x 10^-13 J :biggrin: thank you and also is the rest energy of a proton 0.938 or 938 becuase for an electron its 0.511


938.28, according to google :tongue: Protons are much (4 orders of magnitude) more massive than electrons, so it makes sense their rest energy is much higher as a result (4 orders of magnitude plus some change, in fact...a coincidence? Not likely :wink: ).
(edited 4 years ago)
Original post by artful_lounger
938.28, according to google :tongue: Protons are much (4 orders of magnitude) more massive than electrons, so it makes sense their rest energy is much higher as a result (4 orders of magnitude plus some change, in fact...a coincidence? Not likely :wink: ).

thanks. could you also help me with these questions?
1) an atom of argon 37Ar is ionised by the removal of two orbiting
18
electrons what is the charge of this ion

1b)calculate the percentage of the total mass of this ion that is accounted for by the mass of its electrons

2)calculate the ration charge/mass in C/kg for the 236 U nucleus
92
3)in the radioactive decay of a nucleus, a beta plus particle is emitted followed by a y photon of wavelength 8.30 x 10^-13 m
.state the mass in kg of the beta plus particle
.calckate the energy of the photon

4)calculate the minimum amount of energy in j released as radiation energy which a particle of the rest energy of 0.51 MeV meets its corresponding antiparticle

5)an antiparticle and a particle collide with same speed to produce subatomic particles. the total kinetic energy of the two subatomic particles just before the collision is 3.2 x 10^-10 J state why the total energy after the collision is more than 3.2 x 10^-10
5b)in a second collision the kinetic energy was greater than 3.2 x 10^-10 state two possible differences this could make to the subatomic particles produced

6)e- + p > n + Ve
name the fudamental force resonsiible for this interaction

7)give an example of an exchange particle other than w+ or - particle

sorry that theres so many

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