how does light travel in air as it is a transverse wave and transverse wave can't travel through liq or gases?

Question

in my textbook it is mentioned that transverse waves can't travel through liq or gases then how can light or other electromagnetic waves travel through air or water as they are also transverse waves???

Answer 1

Just by seeing, you know that light's transverse waves DO pass through air.
Your textbook was only talking about waves of liquid molecules in liquid, or air molecules in air, and was perfectly correct as far as that goes.
When we are not talking about mechanical disturbances passing through such a medium, the rule doesn't apply. The confusion arises from the fact that, for obvious reasons, we tend to abbreviate the phrase 'mechanical waves of disturbance of water molecules in a water medium through that medium' to just the term 'waves'.

Answer 2

This is because transverse waves inside liquids and gases aren't supported, because it is the *medium* that is being sheared. Because it is very difficult to shear a liquid (in effect, you almost can't by definition) you can't have a transverse wave.

However, light, as has been pointed out already, does not need a medium to travel. It slows down in continuous media because it is continually absorbed and remitted (refracted) by atoms and molecules. So, really it's still travelling in space, but colliding with atoms as it goes along.

Summary: It's not the medium that carries the wave.

Answer 3

your intial premise that em waves only slow down on refraction is basically incorrect. Note - em waves cannot exceed the speed in a vacuum = 3 x 10^8 m/s - they do not require a medium to travel. so they will speed up when going from the Earth's atmosphere into space which of course causes refraction. The tranverse wave is more free to move (as a particle or a wave) when there is nothing to impede it ( hence in a vacuum) - once in a material medium the particles of the medium impede the wave. This is opposite to a sound wave which uses compressions to travel so a denser medium assists the passage by speeding it up =

Answer 4

We now know that light is a wave, however, it was very questionable wether light was a particle or a wave, as it behaves sometimes like particles and sometimes like waves. This is one of the situations in which it behaves like a particle, as it can travel through liquids and gases.

Answer 5

i dont like saying that books can be wrong but urs certainly seems to be wrong.
transverse waves like electromagnetic waves DO NOT NEED a medium like a liquid or gas to travel through but that does not mean that they can't.
electromagnetic waves can travel through vacuum (no medium) and they can travel through liquids and gases and transparent solids.
light can travel through liquids and gases. if it couldn't, where does 'refraction of light' end up?

Answer 6

Light can travel through liquids, mainly because photons are too small for a liquid or gas to have much affect, the photons pass between the spaces between and atoms, and the spaces between elctrons and neclei which is, relatively, huge. I think maybe you misread the book.