Im attempting a problem in relativistic optics thats asking me to write k_x, k_y and k_z in terms of lambda, c, and theta (theta being the angle between a source and an observer, at rest relative to each other). Lamda is the wavelength in this reference frame. I started off using trigonometry to say that { k_x = 2*pi*cos(theta) / lambda } and equivalent but with sin(theta) for k_y but then how do I express k_z ? i cant see hw to it without introducing an angle between the x and z axis!(adsbygoogle = window.adsbygoogle || []).push({});

help please!

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# Decomposition of the wave-vector in terms of wavelength

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