Oersted, The physicist who linked electric and magnetic fields.

 Hans Christen Oersted discovered a link between electric fields and magnetic fields to give birth to electromagnetism. He managed to establish a clear link between the two phenomenon and this is how he did it.

After completing his phd and travelling Europe Oersted began giving lectures privately before picking up momentum and began his own lectures in the university of Copenhagen. During his travels he met another physicist called Johann Ritter, who was one of the few physicists who believed in a link between electricity and magnetic forces. The reason for this conflict in the physics world at the time was due to the idea that electricity and magnetism could not be related as they where completely different forces, but it was known through sailors that whenever the ship was struck by lighting the polarity of the compass would be reversed.

In 1820 as Oersted was setting up a practical to demonstrate an electric circuit to his students made his remarkable discovery. He noticed that his compass, which was pointing north, in line with the earths magnetic field, would shift away from north when held near the electric circuit. What does this mean? 

The conclusion that Oersted came away with is that a flowing electric current can disturb the magnetic field of a compass. Rather than write a lab report on his discovery he gave a lecture on it immediately after discovering this new information. His students looked at him with confused faces and no one believed him. He eventually made a lab report and published it with his results. This made oersted famous over night and sparked a revolution in the ideas of electricity and magnetism. As a result of this experiment it led to the birth of electrodynamics and many new discoveries such as faradays experiments and maxwells equations.

the reason for this blogpost stems from a book I read called, "Why does E = mc^2" by Brian Cox and Jeff Foreshaw, where they derived the famous equation and something that you need to know is Maxwells equations and as they don't go into extreme detail about the equations (apart from assuming the speed of light is a constant, which Einstein did).This is why I am going to go on a journey to discover how Maxwell reached the conclusion to derive his equations in order to gain a deeper understanding of why E=mc^2.