Two co-axial wires one solid and one hollow, each carry the same current I in opposite directions. The radius of the inner wire r1The inner radius of the hollow wire is r2. What is the magnetic induction at a point where r2

Question

Two co-axial wires one solid and one hollow, each carry the same current I in opposite directions. The radius of the inner wire r1The inner radius of the hollow wire is r2. What is the magnetic induction at a point where r2 < r < r1 (A) (μ I/2π r) (B) (μ I/2π r)[r22+r12] (C) (μ I/2π r)[r22-r12] (D) (μ I/2π r)(1/r22+r12)

Tardigrade Admin · Accepted Answer

Here B × 2 π r = μ0 I or B = (μ0 I/2 π r)

Q. Two co-axial wires one solid and one hollow, each carry the same current I in opposite directions. The radius of the inner wire $r_{1}$ The inner radius of the hollow wire is $r_{2}$ . What is the magnetic induction at a point where $r_{2} < r < r_{1}$

$\frac{μ I}{2 π r}$

$\frac{μ I}{2 π r}$ $[r_{2}^{2} + r_{1}^{2}]$

$\frac{μ I}{2 π r}$ $[r_{2}^{2} - r_{1}^{2}]$

$\frac{μ I}{2 π r}$ $\frac{1}{r _{2}^{2} + r _{1}^{2}}$

Here $B \times 2 π r = μ_{0} I$ or $B = \frac{μ _{0} I}{2 π r}$

Q. Two co-axial wires one solid and one hollow, each carry the same current I in opposite directions. The radius of the inner wire r1​The inner radius of the hollow wire is r2​. What is the magnetic induction at a point where r2​<r<r1​

2πrμI​

2πrμI​[r22​+r12​]

2πrμI​[r22​−r12​]

2πrμI​r22​+r12​1​