![]() The current induced in the coil creates another field, in the opposite direction of the bar magnet’s to oppose the increase. ![]() Lenz’ Law: (a) When this bar magnet is thrust into the coil, the strength of the magnetic field increases in the coil. Faraday was aware of the direction, but Lenz stated it, so he is credited for its discovery. The direction (given by the minus sign) of the EMF is so important that it is called Lenz’ law after the Russian Heinrich Lenz (1804–1865), who, like Faraday and Henry, independently investigated aspects of induction. According to Lenz’s law, the emf produced in the coil will drive a current in the direction. Thus, the magnetic field B mag B mag (x ) B mag B mag (x ) pointing to the right increases in the coil. The minus means that the EMF creates a current I and magnetic field B that oppose the change in flux Δthis is known as Lenz’ law. In the top row, the north pole of the magnet approaches the coil, so the magnetic field lines from the magnet point toward the coil. The minus sign in Faraday’s law of induction is very important. The units for EMF are volts, as is usual. This relationship is known as Faraday’s law of induction.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |