Electro magnetic waves travel in a medium with speed of `2xx10^(8)m//sec`. The relative permeability of the medium is `1` find relative permittivity.

Explanation

The speed of electromagnetic waves and in a medium is given by
`v=1/sqrt(muvarepsilon)`
Where `mu and varepsilon` are absolute permeability and absolute permittivity of the medium. We know that, `mu = mu_(0)mu_(r) and varepsilon = varepsilon_(0) varepsilon_(r)`. Hence
`v=1/sqrt((mu_(0)mu_(r).varepsilon_(0)varepsilon_(r)))=1/sqrt((mu_(0)varepsilon_(0)))xx1/sqrt((mu_(r)varepsilon_(r)))`
`v=c/sqrt((mu_(r)varepsilon_(r)))or varepsilon_(r)=c^(2)/(v^(2)(mu_(r))) `
`therefore varepsilon_(r) = ((3xx10^(8))^(2))/((2xx10^(8))^(2)xx1)=2.25`