Electric field of plane electromagnetic wave propagating through a non-magnetic medium is given by E =20 cos (2 × 1010 t -200 x ) V / m. The dielectric constant of the medium is equal to: (. Take .μ r =1)

Question

Electric field of plane electromagnetic wave propagating through a non-magnetic medium is given by E =20 cos (2 × 1010 t -200 x ) V / m. The dielectric constant of the medium is equal to: (. Take .μ r =1) (A) 9 (B) 2 (C) (1/3) (D) 3

Tardigrade Admin · Accepted Answer

Speed of wave =(2 × 1010/200)=108 m / s Refractive index =(3 × 108/108)=3 Now refractive index =√ε r μ r 3=√ε r (1) ⇒ ε r =9

Q. Electric field of plane electromagnetic wave propagating through a non-magnetic medium is given by $E = 20 cos (2 \times 1 0^{10} t - 200 x) V / m$ . The dielectric constant of the medium is equal to :
$($ Take $μ_{r} = 1)$

9

2

$\frac{1}{3}$

3

Speed of wave $= \frac{2 \times 1 0 ^{10}}{200} = 1 0^{8} m / s$
Refractive index $= \frac{3 \times 1 0 ^{8}}{1 0 ^{8}} = 3$
Now refractive index $= ε_{r} μ_{r}$
$3 = ε_{r} (1)$
$\Rightarrow ε_{r} = 9$

Q. Electric field of plane electromagnetic wave propagating through a non-magnetic medium is given by E=20cos(2×1010t−200x)V/m. The dielectric constant of the medium is equal to : ( Take μr​=1)

9

2

31​

3

Speed of wave =2002×1010​=108m/s Refractive index =1083×108​=3 Now refractive index =εr​μr​​ 3=εr​(1)​ ⇒εr​=9

Q. Electric field of plane electromagnetic wave propagating through a non-magnetic medium is given by $E = 20 cos (2 \times 1 0^{10} t - 200 x) V / m$ . The dielectric constant of the medium is equal to :
$($ Take $μ_{r} = 1)$

$\frac{1}{3}$

Speed of wave $= \frac{2 \times 1 0 ^{10}}{200} = 1 0^{8} m / s$
Refractive index $= \frac{3 \times 1 0 ^{8}}{1 0 ^{8}} = 3$
Now refractive index $= ε_{r} μ_{r}$
$3 = ε_{r} (1)$
$\Rightarrow ε_{r} = 9$