Question

The lengths and breadth of a rectangle are `(5.7 +- 0.1)cm and (2.4 +- 0.2)` cm. Calculate area of the rectangle with error limits.

Answer 1

Correct Answer - `(13.7 +- 1.4)sq. cm`
Here, `I = (5.7 +- 0.1)cm, b = (2.4 +- 0.2)cm`
`A = Ixxb =5.7xx2.4 = 13.68sq. Cm.`
= 13.7sq.cm
`(DeltaA)/(A) = +- ((DeltaI)/(I) +(Deltab)/(b)) =+-((0.1)/(5.7) +(0.2)/(2.4))`
`=+-(0.0175+0.0833)`
`DeltaA =+-(0.1008)xx13.7 = +-1.38sq.cm.`
`+- 1.4sq. cm`
Hence area = (1.37+- 1.4)sq. cm