Discover published sets by community

Hans Christian Oersted discovered that electric current affects a magnetic compass. Placing a compass near a wire carrying a current causes the compass needle to rotate, indicating a magnetic field generated by the electric current.

Heinrich Lenz stated that the direction of the current induced in a conductor by a changing magnetic field is such that the magnetic field created by the induced current opposes the initial changing magnetic field. This is summarized as $\epsilon = - \frac{d\Phi}{dt}$, where $\Phi$ is the magnetic flux.

André-Marie Ampère found that the magnetic field in a loop of wire is proportional to the electric current passing through the wire. This law is fundamental in electromagnetism and given by the equation $\oint \vec{B} \cdot d\vec{l} = \mu_0 I$, where $I$ is the current and $\mu_0$ is the vacuum permeability.

J.J. Thomson used cathode rays to discover the electron. He showed that cathode rays were particles with a specific charge-to-mass ratio and could therefore be deflected by electric and magnetic fields.

Edwin Hall discovered that a magnetic field applied perpendicular to the direction of current flow in a conductor would lead to the development of a voltage across the conductor. This Hall voltage is directly proportional to the strength of the magnetic field and current.