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An EM wave from air enters a medium. The...

An EM wave from air enters a medium. The electric fields are
`overset(vec)E_(1)=E_(01)hatx cos[2piv((z)/(c )-t)]` in air and
`overset(vec)E=E_(02)hatx cos [k(2z-ct)]` in medium, where the wave number k and frequency v refer to their values in air. The medium is non-magnetic. If `in_(r_(1))` and `in_(r_(2))` refer to relative permittivities of air and medium respectively, which of the following options is correct ?

A

`(epsi_(r_(1)))/(epsi_(r_(2)))=(1)/(2)`

B

`(epsi_(r_(1)))/(epsi_(r_(2)))=4`

C

`(epsi_(r_(1)))/(epsi_(r_(2)))=2`

D

`(epsi_(r_(1)))/(epsi_(r_(2)))=(1)/(4)`

Text Solution

Verified by Experts

The correct Answer is:
D
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