Magnetic Energy Density In Em Waves — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.
Magnetic Energy Density in EM Waves Applicable to electromagnetic waves and static magnetic fields in vacuum or air where the magnetic permeability is approximately equal to mu 0. Start with energy in an inductor U = 1/2 L I 2 Substitute inductance L for a solenoid (mu 0 n 2 A l) Express current I in terms of B field (B / (mu 0 n)) Divide total energy by volume (A l) to find density Assumes linear, isotropic, and non-dispersive medium (vacuum/air) Neglects relativistic effects in high-energy plasmas Thinking that magnetic energy density is greater than electric energy density in an EM wave (they are equal) Confusing mu 0 (permeability) with epsilon 0 (permissivity)