[SOLVED] Amperes Law 1. The problem statement, all variables and given/known data Deriving the magnetic field through a solenoid. 2. Relevant 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 permeabiability of free space. 3. The attempt at a solution Long integration that we have been give by our teacher, I understand the math. My issue however is not to do with the formula manipulation, but rather with the actual concept underlying this calculation. A look on wikipedia indicated that the problem should in fact be solved using amperes law, however I am unfamiliar with amperes law and would love a conceptual rather than formulaic explanation of the theorem. Unfortunately my high school teacher does not himself understand the concepts behind the equations he teaches, but rather simply copies notes from a textbook, he himself admitting so. In the event that I have used the template incorrectly, or am going about something wrong, I do strongly appoligise, and would appreciate any guidance in going about my query correctly.