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 solenoid of 1200 turns is wound uniformly in a single layer on a glass tube $2 \mathrm{~m}$ long and $0.2 \mathrm{~m}$ in diameter. The magnetic intensity at the center of the solenoid when a current of 2 A flows through it is:
PhysicsMagnetic Effects of CurrentBITSATBITSAT 2023 (Memory Based Paper 2)
Options:
  • A $2.4 \times 10^3 \mathrm{Am}^{-1}$
  • B $1.2 \times 10^3 \mathrm{Am}^{-1}$
  • C $1 \mathrm{Am}^{-1}$
  • D $2.4 \times 10^{-3} \mathrm{~A} \mathrm{~m}^{-1}$
Solution:
1266 Upvotes Verified Answer
The correct answer is: $1.2 \times 10^3 \mathrm{Am}^{-1}$
Given that number of turns, $n=1200$
Current, $\mathrm{I}=2 \mathrm{~A}$
Magnetic field at centre inside the solenoid is given by,
$\mathrm{B}=\mu_0 \mathrm{nI}$
So magnetic intensity at centre of the solenoid,
$\begin{aligned}
& \mathrm{H}=\frac{\mathrm{B}}{\mu_0}=\mathrm{nI}=\left(\frac{1200}{2}\right)(2) \quad\left(\because \mathrm{B}=\mu_0 \mathrm{H}\right) \\
& \mathrm{H}=1.2 \times 10^3 \mathrm{Am}^{-1}
\end{aligned}$

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.