Torque On Current Loop In Magnetic Field


To demonstrate that there is a torque on a current loop in a magnetic field.◙


Torque on coil in magnetic field apparatus.





A few-turn coil is positioned in the magnetic field of a small horseshoe magnet as shown in the photograph. Pushing the switch connects the battery to the coil, passing electrical current through the coil and creating the torque, which is clearly visible as rotation of the coil about its axis. Reversing the coil leads reverses the direction of the torque. 


Lev Vaidman, Torque and force on a magnetic dipole, AJP 58, 978-983 (1990). ◙V. Hnizdo, Comment on "Torque and force on a magnetic dipole" by Lev Vaidman [AJP 58, 978-983 (1990)], AJP 60,◙279-280 (1992).