What is the quark composition of a proton?
Answer and explanation
Correct answer: C. Two up quarks and one down quark
- Step 1: Up quarks have charge and down quarks .
- Step 2: uud gives .
Answer
Two up quarks and one down quark.
Why not the others: One up quark and two down quarks: this is a neutron. Three up quarks: this has charge +2. Two down quarks and one strange quark: this is not a proton.
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