Q: Clarify example of Faraday's law Im wondering if it is possible to induce a high voltage current (above 1k Volts), simply using a falling magnet and a copper wire  - it probably is, but then what does it take to do so.
I've done some small scale tests, with a small magnet, copper wire and trying to match the calculated (induced) current with the measured one. Without success though. Big difference between the measured and calculated. So I'm wondering if I haven't fully grasped Faraday's law of induction?
Let me give an example where I've chosen elements that theoretically induce a high voltage current in a conduction wire as of what I have understood of Faraday's law of induction.
Having this equation for Faraday's law:
$$E = (N * B * A) / \delta t$$
Where
E = Volts(emf)
N = Number of turns in the conducting wire
B = Tesla (Strength of magnet)
A = Area/Cross section of magnet in square meters ($m^2$)
$\delta t$ = Speed/change of induction (how fast the magnet i falling/passing through the copper coil.)
Found a copper coil that has 24K turns.
A magnet (Neodymium N45), with a stregth of 1.32 Tesla
The magnet is cylindrical and has a diameter of 1.75cm (Ø3cm), hence an area of: 0,00962 $m^2$
I thought of dropping the magnet from 3 meters in the air (inside a pipe, to ensure it passes through the coil), and the gravitational force (9.8m/s2) will accelerate the magnet to a speed of 7,67 m/s after that 3 meter fall. I have intentionally ignored the fact that magnet probably would be slowed by "wind" and small bumps against the pipe.
The copper coil (cylindrical) is 10 cm high, hence the magnet will pass through the coil in about 0,01304 sec.
Putting this in the above equation gives:
Volts(emf) = (24000 x 1,32 x 0,00962) / 0,013 = ~2.337 V AC
I then had a physicist throw a small note at me, saying: I should be cautious about applying Faraday's law in non-homogeneous field. However that was without elaboration, but couldn't tell what he meant by that. 
What am I missing? - Besides I know the speed of the falling magnet will be less, because of friction in the tube and a few other factors.
Note: The magnet is kept in the vertical position, because of it's height, it can not flip around inside the tube.
Any clarification of my understanding of Faraday's law is much appreciated.
