Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
A potential difference $V=100 \pm 5 \mathrm{~V}$, when applied across a resistance, gives a current $I=10 \pm 0.2 \mathrm{~A}$. What is the percentage error in $R$ ?
PhysicsMathematics in PhysicsAIIMSAIIMS 2019 (25 May)
Options:
  • A $2 \%$
  • B $5 \%$
  • C $7 \%$
  • D $8 \%$
Solution:
1216 Upvotes Verified Answer
The correct answer is: $7 \%$
Potential difference is $V=100 \pm 5 \mathrm{~V}$
Current is $I=10 \pm 0.2 \mathrm{~A}$.
Percentage error in voltage is obtained as
$\frac{\Delta V}{V}=\frac{5}{100} \times 100 \%=5 \%$
Percentage error in current is obtained as
$\frac{\Delta I}{I}=\frac{0.2}{10} \times 100 \%=2 \%$
Using, $R=\frac{V}{I}$, the percentage error in resistance is calculated as $R=5 \%+2 \%=7 \%$.

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.