### Subject: maglev - the em drag between a moving conductor and a magnet

Date: Sat Apr 30 13:27:00 2005
Posted by abdul
Grade level: teacher/prof School: sam tet
City: Ipoh State/Province: Perak Country: Malaysia
Area of science: Physics
ID: 1114885620.Ph
Message:
```
I am doing a STUDY of EM drag force between a moving conductor and a permanent
magnet. I understand that a conductor moving with a velocity v over a permanent
magnet will experience a REPULSIVE force.  The formula for that force is as
follows:

Lift force = (Mu*I*I/4*pi*h)(v*v/(v*v + w*w))

Drag Force = (w/v)*Lift Force

w=2/(mu*sigma*delta)

Mu = magnetic permeabilty of vacum
I = Current generated in conductor
h = separation between permagnet and conductor
v = velocity of conductor
w = charateristic velocity
sigma = conductivity of conductor
delta = conductor thickness.

w = The velocity where the EM DRAG is maximum
w=2/(mu*sigma*delta)

The formula shows that the charateristic velocity  varies inversley with the
thickness of the conductor.  This means:
1.  If thickness approaches ZERO w approaches infinity!
2.  If thickness approaches infinity w approaches zero!

Are these deductions correct.? What part does the EDDY CURRENT penetration
depth plays in this?

```

Re: maglev - the em drag between a moving conductor and a magnet

Current Queue | Current Queue for Physics | Physics archives