Search any question & find its solution
Question:
Answered & Verified by Expert
Two long parallel straight metal wires A and B carrying currents $12 \mathrm{~A}$ and $36 \mathrm{~A}$ respectively, in the same direction are separated by $50 \mathrm{~cm}$. The point relative to $A$, where the resultant magnetic induction between the two wires due to the currents is zero, will be
Options:
Solution:
1105 Upvotes
Verified Answer
The correct answer is:
$12.5 \mathrm{~cm}$
Suppose at $\mathrm{P}, \mathrm{B}=0$
So, $\mathrm{B}=0$
$$
\begin{aligned}
& \Rightarrow \frac{\mu_0 \mathrm{i}_1}{2 \pi \mathrm{r}}+\frac{\mu_0 \mathrm{i}_2}{2 \pi(0.5-\mathrm{r})}=0 \\
& \Rightarrow \frac{\mathrm{i}_1}{\mathrm{r}}+\frac{\mathrm{i}_2}{0.5-\mathrm{r}}=0 \\
& \Rightarrow \frac{12}{\mathrm{r}}+\frac{36}{0.5-\mathrm{r}} \\
& \Rightarrow 0.5-\mathrm{r}=3 \mathrm{r} \\
& \Rightarrow 0.5=4 \mathrm{r} \\
& =\mathrm{r}=\frac{1}{8} \mathrm{~m}=12.5 \mathrm{~cm}
\end{aligned}
$$
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.