Question

A physical quantity is measured as Q = (2.1±0.5) units. Calculate the percentage error in
(a) Q2
(b) 2Q

Answer 1

(i) % error in q =  \frac{0.5}{2.1} \times 100= 23.81%

   there fore % error in  q^{2}  = 2 \times 23.81 = 47.62%

(ii) % error in 3q = % error in q = 23.81%

i have not written this i copied it from another expert's answer on different question...