(Solved): A copper solenoid is set to magnetize a copper-nickel bar \( (0.0018 \mathrm{at} \% \mathrm{Ni}) \ ...

A copper solenoid is set to magnetize a copper-nickel bar \( (0.0018 \mathrm{at} \% \mathrm{Ni}) \). With a \( 12.5 \mathrm{~A} \) current, a diameter of \( 0.6 \mathrm{~cm} \), the permeability of the alloy is \( 2.06 \mathrm{E}-3 \mathrm{H} / \mathrm{m} \) and an inductance of \( 1.37 \mathrm{~A} \mathrm{H} / \mathrm{m}^{2} \). What is the turns to length \( (1 / \mathrm{m}) \) ratio of the solenoid? (3 marks)