2024 Re-NEET Units and MeasurementsError analysis - propagation of errors Medium Question 10 of 53 in Units and Measurements

In an electrical circuit, the voltage is measured as $V=(200\pm4)$ volt and the current is measured as $I=(20\pm0.2)$ A. The value of the resistance is:

A $(10\pm4.2)\ \Omega$
B $(10\pm0.3)\ \Omega$
C $(10\pm0.1)\ \Omega$
D $(10\pm0.8)\ \Omega$

The answer is B.

Solution

$R=\dfrac{V}{I}=\dfrac{200}{20}=10\ \Omega$. $\dfrac{\Delta R}{R}=\dfrac{\Delta V}{V}+\dfrac{\Delta I}{I}=\dfrac{4}{200}+\dfrac{0.2}{20}=\dfrac{6}{200}$. $\Delta R=\dfrac{6}{200}\times10=0.3\ \Omega$. So $R=(10\pm0.3)\ \Omega$.

Concept Error analysis - propagation of errors

Units and Measurements in past papers

53 questions from this chapter have appeared across 25 exam years.