Q21 · 2024 · Paper 1Simple familiar3 marks
QUESTION 21 (3 marks)
Describe the particle interaction shown.
WORKED SOLUTION
3 marksQCAA guide · typeset solution
ANSWER
See worked solution below.
Worked solution
The Feynman diagram represents the interaction between an
electron and a positron. During this interaction the two particles
are annihilated into a photon. The photon will then ‘pair produce’
another electron and positron.
• identifies that the interaction involves an
electron and a positron [1 mark]
• identifies that a photon is created through
annihilation [1 mark]
• describes ‘pair produced’ creation of
another electron and positron [1 mark]
One QCAA sample method typeset for web; criterion wording is adapted from the official marking guide.
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