Physics

Problem

In a medium with relative permeability

μ_r = 4

and relative permittivity

ε_r = 9

, the electric field is described by

E(x,t)=150 \sin(1.5\times10^{7} x - ω t)\,\text{N C}^{-1}

. Calculate the angular frequency

ω

(in rad s⁻¹) required so that the expression represents a plane electromagnetic wave propagating in that medium. (

c=3.0\times10^{8}\,\text{m s}^{-1}

) a)

1.5\times10^{15}

4.5\times10^{15}

7.5\times10^{14}

1.3\times10^{14}