Question

the speed of em wave in a medium whose dielectric constant is 2.25 & relative permeability 4 is equal to

Answer 1

$$\begin{gathered} v=\frac{1}{\sqrt{{\mu }_0{\mu }_r{\epsilon }_0{\epsilon }_r}}=\frac{1}{\sqrt{4\pi \times {10}^{-7}\times 4\times 8.85\times {10}^{-12}\times 2.25}} \\ v=\frac{1}{\sqrt{1000.404\times {10}^{-19}}}=\frac{1}{10.001\times {10}^9}=0.0999\times {10}^8=0.9\times {10}^{8}m/s \end{gathered}$$