Question

The voltage across a conductor is measured as $V=(100\pm 4)V$ and electric current through it is measured as $(5\pm 0.2)A.$ The maximum percentage error in the calculation of resistance is

• A. $2\%$
• B. $8\%$
• C. $4\%$
• D. $10\%$

Answer 1

The correct option is B $8\%$

$R=\frac{V}{l}$
$\therefore \frac{\Delta R}{R}\times 100\%=(\frac{\Delta V}{V}+\frac{\Delta l}{l})\times 100\%=8\%$