Question 241: Units , Dimensions and Error Analysis

Question

The resistance R = $${V \over I}$$, where V = (50 $$\pm$$ 2)V and I = (20 $$\pm$$ 0.2)A. The percentage error in R is 'x'%. The value of 'x' to the nearest integer is _________.

Accepted Answer

$$R = {V \over I}$$
$${{\Delta R} \over R} 	imes 100 = {{\Delta V} \over V} 	imes 100 + {{\Delta I} \over I} 	imes 100$$
% error in $$R = {2 \over {50}} 	imes 100 + {{0.2} \over {20}} 	imes 100$$
% error in R = 4 + 1
$$ 	herefore $$ % error in R = 5%

Units , Dimensions and Error Analysis

The resistance R = ${V \over I}, where V = (50 \pm 2)V and I = (20 \pm$ 0.2)A. The percentage error in R is 'x'%. The value of 'x' to the nearest integer is _________.

Choose the correct answer: