Light and other EM wavelengths experiment

[layman77]

Posted this here because I was thinking light is a quanta of energy, was wondering if I should've posted it in classical physics.

 

I've heard that every spectra of the EM spectrum (radio waves/microwaves/visible light/infrared,etc) has a certain wavelength, but I'm just curious about the research that led to this. This has been experimentally verified correct? What is the experiment you do to show this?

 

And, each of the spectra on the EM spectrum, all them is a form of electro-magnetic radiation, and electric and magnetic fields are at right angles to each other, is there an experiment to show this too?

[swansont]

Light is not the quanta of energy. Light has energy, but many things that are not light have energy, too. Many different wavelengths of the EM spectrum have been observed; with visible light it can be shown with a diffraction grating or prism and various atomic sources which have specific transition wavelengths.

 

Electric and magnetic fields being perpendicular can be shown with polarized light, and excitation of magnetic or electric dipole transitions, when the atoms are spin-polarized. You don't get the transition occurring for the orthogonal polarization.

[Mr Skeptic]

Posted this here because I was thinking light is a quanta of energy, was wondering if I should've posted it in classical physics.

 

Photons are the quantum of electromagnetic waves (and also contain a quanta of energy).

 

I've heard that every spectra of the EM spectrum (radio waves/microwaves/visible light/infrared,etc) has a certain wavelength, but I'm just curious about the research that led to this. This has been experimentally verified correct? What is the experiment you do to show this?

 

For visible light you could look at a rainbow, or the equivalent made by a prism. For radio waves, tune your radio to a certain station (wavelength).

 

And, each of the spectra on the EM spectrum, all them is a form of electro-magnetic radiation, and electric and magnetic fields are at right angles to each other, is there an experiment to show this too?

 

This is necessary for them to be theoretically allowed (as a solution to Maxwell's equations). The proof that they are so, is that Maxwell's equations work.