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The propagation of radio waves in the earths atmosphere is affected by the ionosphere, the region 75 to 1000 km above the surface of the earth that is ionized by solar and cosmic radiation. Radio waves which are refracted or reflected off the ionosphere are called 'sky-waves'. The region between the earth and the ionosphere effectively forms a 'waveguide' ...

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I suspect Austin was just wondering what it would look like if we could see radio waves. The best analogy I can think of to represent that is to put an arc light from a carbon arc search light without the shroud and reflector on the top of the antenna pole and apply the same wattage. The main difference is that the electromagnetic field of the radio wave ...

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Calculating the path that a light ray takes in a gravitational field is a complicated business, but for the special case of a light ray coming from infinity and escaping to infinity there is a convenient approximate formula for the angle, $\theta$, the light ray is deflected: $$\theta \approx \frac{4GM}{r_0 c^2}$$ Where $M$ is the mass of the ...

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The wavelength does of course remain the same. Think about two circles (representing wavefronts) evolving over time. Their respective radii increase at the same rate, such that the distance between them (the wavelength) always stays the same. Now think about drawing a box of fixed size and placing it over the wavefronts. This represents your detector (or ...

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A accelerated electron emit photons which travel through space without any changes until they will be received by another particle. Radio waves are made from a lot of accelerated electrons in an antenna rod. The radio wave one detect is modulated from antenna generator and contains the photons from the periodically accelerated electrons. The radio wave get ...

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Since the emitter is a point, the wave will never get "flatter". It will always look like a dipole pattern (for the non-relativistic case, for the relativistic case the forward and backward lobes become asymmetric, I believe, with a strong amplification of the emission into the forward cones, which should also become narrower). I think you are mistaking your ...

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