Question

The average magnetic energy density of an electromagnetic wave of wavelength l travelling in free space is given by

• A. $\frac{B^{2}}{2\lambda}$
• B. $\frac{B^{2}}{2\mu_{0}}$
• C. $\frac{B^{2}}{\mu_{0}\lambda}$
• D. $\frac{B}{\mu_{0}\lambda}$

Answer 1

Answer: (B)

The average magnetic energy density of an electromagnetic wave travelling in free space is
$u_{B}=\frac{B^{2}}{2\mu_{0}}$