A direct current I flows along the length of an infinitely long straight thin walled pipe, then the magnetic field

Question

A direct current I flows along the length of an infinitely long straight thin walled pipe, then the magnetic field (A) is zero only along the axis of the pipe (B) is zero at any point inside the pipe (C) is maximum at the centre and minimum at the edges (D) is uniform throughout the pipe hut not zero

Tardigrade Admin · Accepted Answer

Required arrangement is shown in figure. According to Ampere's circuital law.

For an internal point,

r < R

B_{internal} = \frac{μ _{0} ( 0 )}{2 π r} = 0

For a point on the pipe,

r = R

B = \frac{μ _{0} I}{2 π r}

For an external point,

r < R

B_{extemal} = \frac{μ _{0} I}{2 π r}

Q. A direct current I flows along the length of an infinitely long straight thin walled pipe, then the magnetic field

is zero only along the axis of the pipe

is zero at any point inside the pipe

is maximum at the centre and minimum at the edges

is uniform throughout the pipe hut not zero

Required arrangement is shown in figure. According to Ampere's circuital law. For an internal point, r<R Binternal ​=2πrμ0​(0)​=0 For a point on the pipe, r=R B=2πrμ0​I​ For an external point, r<R Bextemal ​=2πrμ0​I​

Q. A direct current $I$ flows along the length of an infinitely long straight thin walled pipe, then the magnetic field

Required arrangement is shown in figure. According to Ampere's circuital law.

For an internal point, $r < R$
$B_{internal} = \frac{μ _{0} ( 0 )}{2 π r} = 0$
For a point on the pipe, $r = R$
$B = \frac{μ _{0} I}{2 π r}$
For an external point, $r < R$
$B_{extemal} = \frac{μ _{0} I}{2 π r}$