A Solenoid Is Wound with 970 Turns on a Form

Multiple Choice

A solenoid is wound with 970 turns on a form 4.0 cm in diameter and 50 cm long.The windings carry a current I in the sense that is shown in the figure.The current produces a magnetic field,of magnitude 4.3 mT,near the center of the solenoid.Find the current in the solenoid windings.(μ₀ = 4π × 10^-7 T • m/A)

A) 1.8 A
B) 1.5 A
C) 1.3 A
D) 2.2 A
E) 2.0 A