Question

Resistance R=V/I where V = (100+ - 5) volt and I = (10 +-0.2) A. Find resistance with error limit and percentage error in R.

Answer 1

Here, $$\begin{gathered} V=\left(100\pm 5\right)volts \\ I=\left(10\pm 0.2\right)A \\ Resis\tan ce,R=\frac{V}{I}=\frac{100}{10}=10\Omega \\ \frac{∆R}{R}=\pm \left(\frac{∆V}{V}+\frac{∆I}{I}\right) \\ =\pm \left(\frac{5}{100}+\frac{0.2}{10}\right)=\pm \left(\frac{7}{100}\right)=\pm 0.07 \\ ∆R=\pm 0.07\times R=\pm 0.07\times 10=\pm 0.7\Omega \\ Resis\tan cewitherrorlimitR=\left(10\pm 0.7\right)\Omega \\ PercentageerrorinR=\frac{∆R}{R}\times 100=\pm 0.07\times 100=\pm 7percent \end{gathered}$$