Thanks to Brian Whatcott for the non-relativistic and engineering details of this problem and David Bowman for the special relativity theoretical correction. I'm curious if anyone can estimate the relative importance of the radiation and general relativity corrections. Including radiation must result in a higher initial electron velocity to supply the extra required initial KE. But it's been too many years for me to remember how to calculate the magnitude of the radiation, and I have no idea what general relativity does.
Don
Dr. Donald Polvani
Adjunct Faculty, Physics, Retired
Anne Arundel Community College