Ans. NMR spectroscopy is based on the principle of nuclear magnetic resonance, where atomic nuclei with an odd number of protons or neutrons exhibit a magnetic moment. By subjecting a sample to a strong magnetic field and then applying radiofrequency pulses, NMR spectroscopy measures the absorption and emission of electromagnetic radiation by these atomic nuclei. This technique provides detailed information about the chemical environment, connectivity, and dynamics of molecules, making it valuable for structural elucidation and studying molecular interactions.