An electromagnetic wave has an electric field given by
e? (y, t)=[3.90×105v/mcos(ky−(1.200×1013ra d/s)t)]k^
in which direction is the wave traveling? what is the wavelength of the wave?

λ = 157 μm

Explanation:

given,

now,

ω = 1.2 x 10¹³ rad/s

f = 1.91 x 10¹² Hz

determine the wavelength of the E M wave

   λ = 1.57 x 10⁻⁴ m

   λ = 157 x 10⁻⁶ m

   λ = 157 μm

hence, the wavelength of the wave is equal to λ = 157 μm

d is the correct answer

the entire statement is true and correct.  

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