The electric field in an electromagnetic wave is given by E =56.5 sin ω( t - x / c ) NC -1. Find the intensity of the wave if it is propagating along x-axis in the free space. (Given ε0=8.85 × 10-12 C 2 N -1 m -2 )

Question

The electric field in an electromagnetic wave is given by E =56.5 sin ω( t - x / c ) NC -1. Find the intensity of the wave if it is propagating along x-axis in the free space. (Given ε0=8.85 × 10-12 C 2 N -1 m -2 ) (A) 5.65 Wm -2 (B) 4.24 Wm -2 (C) 1.9 × 10-7 Wm -2 (D) 56.5 Wm -2

Tardigrade Admin · Accepted Answer

I =(1/2) ε0 E 02 c I =(1/2) ×(8.85 × 10-12)(56.5)2 ×(3 × 108) = 4.24 Wm-2

Q. The electric field in an electromagnetic wave is given by $E = 56.5 sin ω (t - x / c) N C^{- 1}$ . Find the intensity of the wave if it is propagating along $x$ -axis in the free space. (Given $ε_{0} = 8.85 \times 1 0^{- 12} C^{2} N^{- 1} m^{- 2}$ )

$5.65 W m^{- 2}$

$4.24 W m^{- 2}$

$1.9 \times 1 0^{- 7} W m^{- 2}$

$56.5 W m^{- 2}$

$I = \frac{1}{2} ε_{0} E_{0}^{2} c$
$I = \frac{1}{2} \times (8.85 \times 1 0^{- 12}) (56.5)^{2} \times (3 \times 1 0^{8})$
$= 4.24 W m^{- 2}$

Q. The electric field in an electromagnetic wave is given by E=56.5sinω(t−x/c)NC−1. Find the intensity of the wave if it is propagating along x-axis in the free space. (Given ε0​=8.85×10−12C2N−1m−2 )

5.65Wm−2

4.24Wm−2

1.9×10−7Wm−2

56.5Wm−2