Final answer:
Nuclear magnetic resonance (NMR) is a phenomenon that occurs when an externally applied magnetic field interacts with the nuclei of certain atoms. By utilizing radio frequency signals, NMR can produce resonances and is utilized as both an analytical tool and in magnetic resonance imaging (MRI) for detailed imaging.
Step-by-step explanation:
Nuclear magnetic resonance (NMR) is a phenomenon in which an externally applied magnetic field interacts with the nuclei of certain atoms. When placed in an external magnetic field, these nuclei align into two energy states based on their spin orientation. By using an external radio frequency signal, the orientation of the nuclei can be flipped, allowing for the absorption and reemission of specific frequencies. NMR is used as an analytical tool, and it has also been developed into magnetic resonance imaging (MRI) for producing detailed images.