Physics II - B14

Magnetic Force Between Two Parallel Conductors
Magnetic Field for a Long, Straight Conductor
Magnetic Field for a Circular Current Loop
Magnetic Field Lines for a Loop
Ampere’s Law
Long Wire with Finite Thickness
Magnetic Field of a Toroid
Magnetic Field of a Solenoid

Magnetic Force Between Two Parallel Conductors

\[\vec F_1 = I_1\vec l \times \vec B_2\] \[\to F_1 = I_1lB\] \[B_2 = \frac{\mu_0I_2}{2\pi a}\] \[\frac{F_1}{l} = \frac{\mu_0I_1I_2}{2\pi a} = \frac {2\times10^{-7} (N)}{1(m)} = \frac{\mu_0 (1A)^2}{2\pi (1m)}\]

$\Rightarrow$ the definition of Ampere

Parallel conductors carrying currents in the same direction attract each other, and parallel conductors carrying currents in opposite directions repel each other.