Question

The resistance is $R=\frac{V}{I}$ where V = 100 $\pm$ 5 Volts and I = 10 $\pm$ 0.2 amperes. What is total error in R ?

• A. 5%
• B. 7%
• C. 5.2 %
• D. $\left(\frac{5}{2}\right)\%$

Answer 1

Answer: (B)

7%

$\frac{\Delta R}{R}\times 100=\frac{\Delta V}{V}\times 100+\frac{\Delta l}{l}\times 100$

$=\frac{500}{1000}\times +\frac{0.2}{10}\times 100=5+2=7\%$