An electromagnetic coil is an electrical conductor such as a wire in the shape of a coil, spiral or helix. Electromagnetic coils are used in electrical engineering, in applications where electric currents interact with magnetic fields, in devices such as inductors, electromagnets, transformers, and sensor coils.
Causes of lower back spasms. Back spasms can be the result of injuries to the muscles, tendons, and ligaments in the back or it can be related to more serious medical conditions. Heavy lifting is a common cause of back spasms. Any activity that puts excessive strain on the muscles and ligaments in the lower back can cause an injury.
Muscle spasms and cramps occur when a muscle contracts involuntarily and painfully. There are a number of causes of spasms, ranging from nutritional deficiency to serious nervous system conditions. If you experience sharp, extremely painful muscle spasms in your neck or back, you should see a physician, as these can be symptoms of a ruptured or bulging disc in your spine.