What is the unit of frequency ?

Which part of the electromagnetic spectrum transfers the most energy ?

Which have the longer wavelengths , microwaves or radio waves ?

How are radio waves produced ?

What happens to the wavelength if a wave source is moving away from you ?

Which galaxies are moving fastest ?

How does red-shift show that the universe is expanding ?

What is the Big Bang theory ?

What happens to the wavelength of radiation as it changes from gamma to microwaves ?