Q 11-01-026NEETEAMCET 2014 (Medical)Top questionEasy
If the absolute errors in two physical quantities $A$ and $B$ are $a$ and $b$ respectively, then the absolute error in the value of $A - B$ is
Answer: (D) $a + b$
For both a sum and a difference, the maximum possible absolute errors add:
$$Z = A \pm B \;\Rightarrow\; \Delta Z = \Delta A + \Delta B = a + b$$
Errors never cancel in the worst case, even when the quantities are subtracted. This is a very common trap.
Solution by Sreeraj P, M.Sc Physics