I decided to peek into the NMR section of my spectroscopy book, and I found out lots of interesting stuff. And along with the interesting stuff, I did come along some stuff that I didn't understand.
My book tells me this (not copied word-for-word):
Under the presence of a magnetic field, the two spin states of the nuclei split up, and if a correct wavelength of light is incident upon the sample, the nuclei get excited to a higher state.
In the above scenario, I believe light behaves as particles, wherein a photon of light collides with a nuclei, and push it to higher spin states.
There's another thing my book says:
Under the presence of a magnetic field, the nuclei begin to precess (wobble like a spinning top). If an incoming electromagnetic radiation has the same frequency as the nuclear precession, resonance occurs and the light is absorbed.
In this case, light behaves as a wave. It's the oscillating electromagnetic fields that are resonating the nuclei, and causing them to absorb the energy.
Out of the two cases that I mentioned, which is the one that actually happens? Is it resonance or spin excitation?