This following applet is [b] Current Loop in magnetic field (How motor works!)[/b]
Created by prof Hwang Modified by Ahmed
Original project [url=]Current Loop in magnetic field (How motor works!)[/url]

This simulation shows a current loop in uniform magnetic field.
The brown arrows show the force due to magnetic field on the loop.
\vec{F}= q \vec{v} \times \vec{B} or \vec{F}= I \int d\vec{\ell} \times \vec{B}
The magnetic field in in the +Z direction if Bz>0.
Then ,torque for the loop is calculated from definition \vec{\tau}=\vec{r}\times\vec{F}

Because the current flow in the same counter-clockwise direction.
The force on the loop change sign during each helf cycle.
If we current reverse direction during each helf cycle, the following device can turn into a motor.
A voltage source is needed in the loop to drive the current.

/htdocs/ntnujava/ejsuser/37048/users/br/ahmed/currentloopinb2_pkg/currentloopinb2.propertiesFull screen applet or Problem viewing java?Add to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License
Download EJS jar file(1666.7kB):double click downloaded file to run it. (41 times by 16 users) , Download EJS source (2 times by 2 users) View EJS source