Im just an ordinary guy with a question, dont know mych about physics.. here is my question..

How do we know that light travels in waves compared to a forward circular motion?

It undergoes interference and diffraction, which are wave behaviors

19 minutes ago, Ian Martin said:

Im just an ordinary guy with a question, dont know mych about physics.. here is my question..

How do we know that light travels in waves compared to a forward circular motion?

What is a "forward circular motion"? Do you mean rolling along like a wheel? Or maybe like a corkscrew?

16 minutes ago, Ian Martin said:

a forward circular motion?

Isn't this a contradiction in terms?

What do you actually mean?

Like a spring

Polarising filters may be relevant.

2 hours ago, Ian Martin said:

Like a spring

Like circularly polarised light?

I assumed he meant 'radial'.
emanating from a central point outward.
Maybe not.

Light is an electromagnetic wave  , which can be seen by the bending of the polarisation of the light when it passes through a magnetic field . But  light is absorbed / emmited in photons which are particles with quantisized energy(factor of a constant).This is called quanta . So light has a dual nature , it is not  a wave , not a particle but both wave and particle .