Consider a solenoid with 55 turns per centimetre, a radius of 1.05 cm and a current of 0.124 A. (a) Find the magnetic field at the centre of the solenoid. (b) What current must a long, straight wire carry to have the same magnetic field as that found in (a)? Let the distance from the wire be the same as the radius of the solenoid. (c) Compare the magnetic fields produced by the two geometries; the solenoid and the long straight wire.