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### Course: Physics archive>Unit 10

Lesson 5: Discovery of electromagnetism

# Discovery of electromagnetism

Hans Christian Ørsted made this famous observation in 1819. Created by Brit Cruise.

## Want to join the conversation?

• 'Why did the needle move?' Was it because when the two ends were connected there was an electric current or something which generates a magnetic field?
• yes, he was giving an example of electromagnetism.
• Again, is it possible to determine the direction of the North by observations made in this video? Can we know the direction of the current flow by observing in which direction the needle starts to spin? Maybe we can figure it out from the previous video with the magnet? Could we figure out the - and the + connections on the 6V power source if they weren't already marked?
• But then according to the video, is North on the left or on the right? ;) Of course, technically it's on the both sides (earth is round), but which side is closer to the North Pole? My question was if it is possible to derive these answers just from the video.
• How is Electromagnetism important?
• Without it you can't think. Your heart would not beat and you dont have cool electric tools.

Another way to think about it. Light is a electromagnetic wave too. A lot of people haven't use for electromagnetism. But it's surrounding us like the air you breath.
• Is that only applicable with AC current?
• The needle seems to move because of the electric field somehow, but when the needle settles down, does it point in a certain direction related to the direction of the battery?
(1 vote)
• what is one way the discovery of magnetism and the invention of the compass affected our ability to explore Earth?
(1 vote)
• vastly improved navigation and chartology became possible.
(1 vote)
• 'Why did the needle move?'It was because when the two ends were connected there was an electric current which generates a magnetic field?
(1 vote)
• is this discovery an accident?