What Is the Energy Density in the Magnetic Field 25

Multiple Choice

What is the energy density in the magnetic field 25 cm from a long straight wire carrying a current of 12 A? (μ₀ = 4π × 10^-7 T ∙ m/A)

A) 7.3 × 10^-5 J/m³
B) 3.7 × 10^-5 J/m³
C) 3.6 × 10^-4 J/m³
D) 1.2 × 10^-4 J/m³
E) The density cannot be determined without knowing the volume.