In an electrical circuit, the voltage is measured as $V=(200 \pm 4)$ volt and the current is measure

Question

In an electrical circuit, the voltage is measured as $V=(200 \pm 4)$ volt and the current is measured as $I=(20 \pm 0.2) \mathrm{A}$. The value of the resistance is

Professor PC Thomas Classes · Answer

(b) : Given, voltage, $(V)=(200 \pm 4) V$ current, $(I)=(20 \pm 0.2) \mathrm{A}$ resistance, $(R)=\frac{V}{I}=\frac{200}{20}=10 \Omega$ Now, error in $R$ is given by, 
$ \begin{aligned} & \frac{\Delta R}{R}=\frac{\Delta V}{V}+\frac{\Delta I}{I}=\frac{4}{200}+\frac{0.2}{20}=0.03 \ & 	herefore \quad \Delta R=R 	imes 0.03=10 	imes 0.03=0.3 \Omega \end{aligned} $
 So, the value of Resistance is $(10 \pm 0.3) \Omega$