A Wire of Diameter D = 1 Mm Is Wrapped

Multiple Choice

A wire of diameter d = 1 mm is wrapped around a cylindrical core of radius R = 5 cm and length l = 30 cm to build a solenoid. What is the energy stored in this solenoid when a current I = 0.2 A passes through it?

A) 1.2 × 10^-4 J
B) 9.6 × 10^-4 J
C) 4.8 × 10^-4 J
D) 2.4 × 10^-4 J
E) 0.6 × 10^-4 J