- Consider the electric field traveling through empty space \vec{E}=(2800 \mathrm{~N} / \mathrm{C}) \cos \left(\left(\frac{4 \times 10^{15}}{\mathrm{~s}} t-k y\right) \hat{x}\right. A) What is the spatial frequency of this wave? B)

What is the wavelength of this wave? C) What is the direction of propagation of this wave? D) What is the frequency of this wave measured in Hz? E) What is the irradiance of this electromagnetic wave? F) Is this electromagnetic wave visible to humans? Justify your answer. G) What is the direction of the electric force that this field would exert on charged particles in its path?