Hello Mike,

 MvdV>> If it did that would be a violation of the law of conservation of
 MvdV>> momentum.


 > The electron gains momentum when it leaves the cathode and
 > returns it when it arrives at the plate. The two direction
 > arrows cancel so momentum is conserved.

And as a result, there is no net force either.

Not from the electrons anyway.

But I understand you were actually referring to fotons emitted by the tube.
Yes, if they are not emitted omnidirectional a net force can result from
that. What you have then is a foton rocket. The momentum gained by the
rocket is compemsated for by the momentum carried away by the fotons.

Cheers, Michiel

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