7. Propagation vector of a plane wave A wave is travelling through free space with a propagation vector K = 6.283(i + j)/√2 m-¹. (i) Write down expression for the electric field E associated with this vector K. [1 mark] (ii) Assume that E is along the z-axis, explain meaning of the condition K E = 0. [1 mark] (iii) Use Faraday's law to find expression for the respective magnetic field B. [2 marks] (iv) Calculate the wavelength this electromagnetic wave described in (i)-(ii). [1 mark] [5 marks]