Energy Density in a Magnetic Field: A large electromagnet has a 22 T magnetic field between its poles. What is the magnetic energy density in that region of space? (?0 = 4? × 10-7 T ? m/A)
A. 190 J/cm3
B. 88 J/cm3
C. 240 J/cm3
D. 30,000 J/cm3
Answer: A
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