In: Physics
(i) Find the magnitude of magnetic field inside a long, ideal solenoid of length L, with N turns and carrying current i. Demonstrate your knowledge of Ampere’s Law by constructing any relevant Amperian loop and integrating along its length. (ii) Two long solenoids that are coaxial, each carry current i, but in opposite directions. The inner solenoid with radius a has n1 turns per unit length, while the outer solenoid with radius b has n2 turns per unit length. Now apply the magnetic field expression you just derived to find the magnetic field inside the inner solenoid.