Practice question · Multiple choice
Independent errors add in quadrature rather than linearly. Why does that make the total smaller than the plain sum?
Hints
- Ask how likely it is that every error takes its maximum in the same direction.
- Independence is doing the work here.
Show the answer
C. Because independent errors cancel as often as they reinforce
Why
Random errors partially cancel. That is also why the rule fails for SYSTEMATIC errors, those are correlated, so they do add linearly.
Practise Propagation of Errors
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