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Summary questions on particle physics

1.  Consider this neutral atom:


(a)  Name the constituents of the atom and state how many of each are present
(b)  Use a data sheet to calculate the charge to mass ratio of the two charged components of the atom.
(c)  Nitrogen has several isotopes - explain the term isotope

2. Calculate the number of constituents of the following atoms:

(a)   27                        (b)   64       2+               (c)   4       2+               (d)  17       2-
            Si                                  Cu                              He                               O
14                                 29                                2                                  8

3.  (a)  Name the two groups that Hadrons can be divided into
(b)  State the number of quarks in each of these two groups

     Describe the arrangement of the quarks in:
(c) protons  (d)  neutrons  (e)  pions  (f)  kaons

4.   What distinguishes Hadrons from other particles?

5.  Name 2 Leptons and their corresponding anti-particle.

6.  What distinguishes Leptons from other particles?

7.  A stationary neutron can decay as shown:  
    n     ->     p   +    e-     +    -v-

(a)  Name -vand determine its proton number and the nucleon number and , in the light of your answers, state, giving your reasoning, one property you would expect of this particle.

(b)  Two varieties of quarks are the up and the down.  What change in quark structure must occur when a neutron changes into a proton?

(c)  Which of the four interaction forces are responsible for the above?

(d)  Given that a quarks can only have a charge of + or - e/3  or  + or - 2e/3,  determine the charges on the u and d quarks - and give your reasoning.

8.  (a)  Draw a Feynman diagram to represent Beta - decay.
(b)  Describe in as much detail as possible each stage of the decay
(c)  Explain carefully how charge is conserved at each stage of the decay.
(d)  Redraw the diagram showing the quark transformation, and explain how charge is again conserved. 
(e)  Use the data sheet to help you comment upon whether Baryon number and Strangeness are conserved during the quark transformation.

9.   Repeat question 8.  but for Beta + decay.

Answer sheet for these question - it's in Word format - if u have word - if you don't - tough