Now consider a different electromagnetic wave, also described by: Ex (z, t) = Eocos (kz - ω t + φ) In this equation, k = 2π/λ is the wavenumber and ω = 2π f is the angular frequency. In this case, though, assume φ = + 30o and Eo = 1 kV/m. What is the value of Ex (z, t) when z/λ = 0.25 and ft = 0.125?

Question

Sara Edwards

Physics

2 August, 21:40

Now consider a different electromagnetic wave, also described by: Ex (z, t) = Eocos (kz - ω t + φ) In this equation, k = 2π/λ is the wavenumber and ω = 2π f is the angular frequency. In this case, though, assume φ = + 30o and Eo = 1 kV/m. What is the value of Ex (z, t) when z/λ = 0.25 and ft = 0.125?

+1

Answers (1)

Know the Answer?

Dax Zimmerman · Answer 1

Ex (z, t) = Eocos (kz - ω t + φ)

k = 2π/λ, ω = 2π f

φ = + 30°, E₀ = 10³ V.

z/λ = 0.25, ft = 0.125

Ex (z, t) = Eocos (2πz/λ - 2πf t + φ)

Putting the values given above

Ex (z, t) = 10³ cos (2π / 4 - 2π x. 125 + 30⁰)

= 1000cos (90⁰ - 45+30)

= 1000 cos 75

=258.8 V.