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Joop asked:


My Optics lecturer said something about how since light travels in a vacuum, you could, potentially, have something travel faster in a different medium, one other than a vacuum.

True or false?

Sandi

wh1t3e4rth asked:


If Electromagnetic Radiation can travel through the vacuum of space then it can travel without a medium, but shouldn’t this be imposable? Or is it true that Electromagnetic Radiation uses the medium of existing magnetic fields, such as earths, distorting these fields much like sound waves do to air? And if so how can this have a direction of travel?

Sherry