Question

4.10P) A plane wave of frequency 900 MHz is and travelling along -y direction with the electric field amplitude of 300 V/m (in vacuum). The value of electric field is -300 V at t=0 and y=0. Choose a magnetic field direction and define the polarization. Write the wave equation of the electric and magnetic field

help me

Answer 1

8 ） sgiven frequency of plane ware = goo MHz OT = 9810 Hz The wave istrave ve istravelling along nyadirection so velocity of wave (W) C (-9) (where c= speed of light) Amplitude of electric field (fo) = 300 m At t=0 $ :0; t = - 300 mm Hence Es E Cos (-ky-wt) =) E = 300 cas (ky tuet kia wave vector of it's direction along the direction of movement (ie, hy). ) where žs - Let direction of magnetic field is direction te Blê). alony We know from electromagnetic theory, -Z MI =-vex B S) É clay) x Blê) E CB(2) direction of E is along 7 Hence along in the heart att

(ə) yo Tud x direction. Hence, we have E = 300 cos (xy + wet) =) < 300.cos (xy + 9710+)(-) Ym that unit vector of [l-ŷ) x t ) 2300 cos(ky +9.net 12 To 드 XE E ) et C 3ro cos(xy + qxot) ( ) tesla 8 3x108 B rów cos (xy +9x10+) (-2) E3 Polonization It i defined as the electric dipate moment per unit votime. It descožbes how a material responds to the applied electric field for a homogeneous, non-dispersine g isotropic dielectric medium the to the electric field

4. e. Þa to -). Xe where Now the wave ) Xe = electroic susceptibility equation for electric & magnetic field are ( 22) & given by E co 2² - 12 co & C.? 872 . 22 . x 300 cars e².82 Me? th с we? co (ky tuet)=0 I from no) ters (kj tuet) + cos(ky. twet)ca -K?) cos (Ky furt) eos (ky t a lot to wave equation for E. Now, wave eq? for 'B' & given by in 8 0

2 o oo -0 0 2 u C² sy? share now cas leytnant) et 9) -x? cm (kyfwet) + cas lay twiet) ad cos (kytuet) 1-3 (9- *?) en (ny t wet) wave eq? for B. z 0 w x ) c?