Question

If the percentage error in measuring length and diameter of a wire is $0.1\%$ each, then the percentage error of the resistance of the wire is :

• A. 0.3%
• B. 0.2%
• C. 0.1%
• D. 0.4%

Answer 1

Answer: (A)

0.3%

Answer 2

The Correct Option is (A): $0.3\%$

$R=\frac{pl}{A}$

$\frac{\triangle{R}}{R}=\frac{\triangle{l}}{l}+2\frac{\triangle{d}}{d}$

=0.3%