A 40.0-mA current is carried by a uniformly wound air-core solenoid with 450 turns, a 15.0-mm diameter,

Question:

A 40.0-mA current is carried by a uniformly wound air-core solenoid with 450 turns, a 15.0-mm diameter, and 12.0-cm length. Compute
(a) The magnetic field inside the solenoid,
(b) The magnetic flux through each turn, and
(c) The inductance of the solenoid.
(d) What If? If the current were different, which of these quantities would change?