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We have a schematic of a problem like here:

https://www.physicsforums.com/threa...ver-a-loop-under-influence-of-b-field.750763/

The conducting rod ab shown in the figure (Figure 1) makes contact with metal rails ca and db. The apparatus is in a uniform magnetic field 1 T, perpendicular to the plane of the figure. The rod has initial velocity u=1m/s mass m=1kg. R of every conductor is 0 ohm

Initial kinetic is 0.5J. because of the Faraday law of induction an infinite force will halt the rod instantaneously in something that pretty much resembles a plastic colission with a wall. Final kinetic energy of the rod is 0.

Initial momentum is 1kg m/s and final momentum is 0.

As there are no losses in the circuit 0.5 joule must have gone to radiating electromagnetic field and the photons of this field must have 1kg m/s of momentum.

Let's suppose that all the photons are emitted directional (not true) in the direction of the initial velocity of the rod.

There is 8 orders of magnitude discrepancy based on the momentum energy relation for the photons emitted E=pc

What am I doing wrong?

Thank you for your time.