Magnetic Shielding If all protons absorbed the same amount of energy in a given magnetic field,not much information could be obtained. But protons are surrounded by electrons that shield them from the external field. Circulating electrons create an induced magnetic field that opposes the external magnetic field => Chapter 13 7Chapter 13 7 Magnetic Shielding • If all protons absorbed the same amount of energy in a given magnetic field, not much information could be obtained. • But protons are surrounded by electrons that shield them from the external field. • Circulating electrons create an induced magnetic field that opposes the external magnetic field. =>