magnetic field

Ships and planes are prepared for Admiral Byrd's third expedition…

Explains electric and magnetic fields, generation of electro-magnetic…

Explains electric and magnetic fields, generation of electro-magnetic…

Explains electric and magnetic fields, generation of electro-magnetic…

Re-enactment of Pierre and Marie Curie at work in their laboratory.…

Producing electric current by spinning a coil attached to a light bulb…