1. The problem statement, all variables and given/known data The figure below shows a plane electromagnetic sinusoidal wave propagating in the x direction. Suppose the wavelength is 56.0 m and the electric field vibrates in the xy plane with an amplitude of 20.0 V/m. (a) Calculate the frequency of the wave. (b) Calculate the magnetic field when the electric field has its maximum value in the negative y direction. (c) Write an expression for with the correct unit vector, with numerical values for Bmax, k, and ω, and with its magnitude in the form B = Bmax cos (kx − ωt). (Assume B is measured in nT, x is measured in m and t in s.) 2. Relevant equations c = 1/(μ0ε0)1/2 c = 299609581 m/s f = c / λ E = Emax cos(kx - ωt) B = Bmax cos(kx - ωt) E max / B max = E / B = c k = 2π/λ ω = 2πf 3. The attempt at a solution I only found the frequency, which is 5.35 x 106 Hz I would like some hints how to find E max then I can just use the third equation listed. I'm thinking that E = Emax cos(kx - wt) and I think E = (20V/m) cos[(0.1121)(x) - (33615041)(t)] where 0.1121 is k (k=2pi / λ) and where 33615041 is ω (ω = 2πf) What would I do with regards to x and t in the equation?