1. The problem statement, all variables and given/known data Q5. A solenoid is 3.0 cm long and has a radius of 0.50 cm. It is wrapped with 500 turns of wire carrying a current of 2.0 A. T 2. Relevant equations Magnetic field of an ideal solenoid = permeability constant (1.257E-6) * current * number of turns 3. The attempt at a solution The given answer is: 4.2 x 10-2 T I don't understand how to get this answer. From what my book says, the magnetic field is independent of cross-sectional area and only deals with semi-infinite solenoids. Please help!