To the list,

Does anyone know the formula for calculating the reverse voltage and
current levels delivered from a MULTI-LAYER coil after a steady state DC
voltage applied to the coil is suddenly interrupted? (if the coil is
able to discharge through a spark gap) I hope I'm stating this properly.
Example:12VDC battery across an air core coil consisting of 20 layers of
#20 copper 2" D (average) and 6" tall. Break the battery connection
suddenly and provide a .025" gap in its place.  

Scott MacGregor
9 South St.
Plainville, MA 02762
Enterprise Engineering Services (EES,Co.)
Fax/Phone 508-695-3717
Power Assist Electric Bicycles
ETC, Inc.
ZAP, Inc.