Ejs Open Source Long Magnet Falling Through solenoid Model Java Applet by lookang, based on a original model by http://www.compadre.org/osp/items/detail.cfm?ID=10327 Magnet Falling Through Ring Model
written by Francisco Esquembre.

/htdocs/ntnujava/ejsuser/14019/users/sgeducation/lookang/MagnetFallingweexmlcoil_pkg/MagnetFallingweexmlcoil.propertiesFull screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ 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(1624.8kB):double click downloaded file to run it. (13 times by 10 users) , Download EJS source View EJS source

adapted to fit the new model of a long magnet made by an array of magnetic dipoles instead of the original model of a single magnet dipole ans also a solenoid made of many coils.

Long Magnet falling through a Solenoid
When a long magnet falls through a Solenoid, current is induced in the Solenoid. This phenomenon is called electromagnetic induction.

According to Faradayís law, the induced emf is proportional to the negative of the rate of change of magnetic flux ?. The direction of the induced current is determined by Lenzís law, the induced current produces magnetic field which tends to oppose the change in magnetic flux that induces such currents.

The voltage induced when a magnet is falling through a Solenoid is simulated in this experiment, where we model the magnet as a vertical set of magnetic 'dipoles'. The current is visualized by very big 'electrons' that move according to the strength of the current.

Please, complete this set of Minds-On questions:
Explain the shape (positive and negative peaks) of the recorded signal.
Why the peaks are not symmetric?
At which moment was the magnetic flux changing most quickly?
What was the total change of magnetic flux during the first half of the magnetís fall - while it was moving in to the coil?
What was the total change of magnetic flux during the second half of the magnetís fall - while it was moving out of the coil?
How could you change the simulation to increase the magnitude of the sign?
This simulation was created as part of the MOSEM2 project.