Answer :
The magnetic field inside a solenoid = μ₀ n i , if radius << length.
n = number of turns per unit length
this is directed parallel to the axis of the solenoid.
the magnetic field outside a solenoid = 0 (nearly)
the magnetic field inside a pipe = 0 as integral of B.dS = μ i and the current enclosed with in a circuital path (closed)is zero inside the pipe... We know that the current (electric charges) reside on top of the outer cylindrical surface (of the conductor). This is according to the circuital law.. Is that Lenz's ?
the magnetic field outside the pipe at a distance d from the axis of the pipe is :
B . 2 π d l = μ i
so B = μ i / (2 π d l ) and it is radially pointing outwards...
n = number of turns per unit length
this is directed parallel to the axis of the solenoid.
the magnetic field outside a solenoid = 0 (nearly)
the magnetic field inside a pipe = 0 as integral of B.dS = μ i and the current enclosed with in a circuital path (closed)is zero inside the pipe... We know that the current (electric charges) reside on top of the outer cylindrical surface (of the conductor). This is according to the circuital law.. Is that Lenz's ?
the magnetic field outside the pipe at a distance d from the axis of the pipe is :
B . 2 π d l = μ i
so B = μ i / (2 π d l ) and it is radially pointing outwards...