I had a long think about the Biot Savert law, and what I can understand from it is the following: It pertains to a length of wire that is so small it can be approximated to be a point
the 1/4pir^2 factor is because at a distance r, all of the flux is being spread across the surface of a sphere...
[SOLVED] Amperes Law
Homework Statement
Deriving the magnetic field through a solenoid.
Homework Equations
dB = mu0/4pi x Idlsintheta/ r^2
where I = current dl= a tiny change in length dB = a tiny change in flux density
sintheta is the angle to the normal r is the radius mu0 is the...