Electromagnetic current

Hans Christian Oerstad, a Danish scientist, discovered that a magnetic needle was deflected by an electric current - electromagnetism. 

Figure 5. Direct current electromagnetic pump for cold trap operations...

Figure 7. Direct current electromagnetic pump in operation at 800°C. (1472°F.)...

A laboratorial scale continuous current electromagnetic pump has been developed and tested at lEAv, using mercury as working fluid. Work is continuing towards the development of a small scale alternating current pump. 

E 376-89 Practice for Measuring Coating Thickness by Magnetic-field or Eddy-Current (Electromagnetic) Test Methods... 

Cylinders are fitted with iron balls and strong magnetic fields are set up in the space between the iron balls on application of an electrical current. Electromagnetic filter is shown in Fig. 11.13. Ferromagnetic impurities are attracted to the magnetic poles and retained. For cleaning, the matrix is demagnetized and the filter is washed out. A removal efficiency of 90% has been reported. 

Rayleigh and Jeans constructed a classical theory of black-body radiation. They defined as their system the set of standing electromagnetic waves that could exist inside a box made of electrically conductive material. An electric field cannot penetrate a perfect conductor (one with zero resistance), because a finite electric field would produce an infinite current. Electromagnetic waves must have nodes at perfectly conducting... 

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