Question

The resistance \[\mathrm{R}=\frac{\mathrm{V}}{\mathrm{I}}\] where V = (100 ± 5) V and I=(10±0.2) A. The percentage error in R is ______.

Options

• 5.2%

• 4.8%

• 7%

• 3%

Answer 1

The resistance \[\mathrm{R}=\frac{\mathrm{V}}{\mathrm{I}}\] where V = (100 ± 5) V and I=(10±0.2) A. The percentage error in R is 7%.

Explanation:

\[\mathbf{R}=\frac{\mathbf{V}}{\mathbf{I}}\]
\[\frac{\Delta\mathrm{R}}{\mathrm{R}}=\frac{\Delta\mathrm{V}}{\mathrm{V}}+\frac{\Delta\mathrm{I}}{\mathrm{I}}=\frac{5}{100}+\frac{0.2}{10}=0.07\therefore\quad\mathrm{Percentage~error:}\frac{\Delta\mathrm{R}}{\mathrm{R}}\times100=7\%\]