Ask Any Question

What causes radio wave at the surface of the earth to hug the earth's surface?

tamburo - 2007-09-27 04:05:35 - Physics

If this bending is due to diffraction how can this be explained?Diffraction requires sharp edges or small apertures.

Best Answer:

Radio waves are like photons and travel in a straight line like light at the speed of light. However wave length is an important consideration. Waves that are very short are very penetrating while longer waves may bounce off a surface (ionosphere). Waves tend to bend when they strike something nearly their own size. Even light 'bends' through tiny slits in a refraction grid.

Answers:

They don't "hug the Earth's surface." If they did, you couldn't communicate with aircraft or spacecraft by radio. Radio waves spread in all directions, including upwards. But some radio waves (shortwave) are reflected off the ionosphere and so can be received beyond line-of-sight.

Radio waves are like photons and travel in a straight line like light at the speed of light. However wave length is an important consideration. Waves that are very short are very penetrating while longer waves may bounce off a surface (ionosphere). Waves tend to bend when they strike something nearly their own size. Even light 'bends' through tiny slits in a refraction grid.