In ENT episode “Divergence” parts go flying off the ship during warp 5. What would happen to something at that speed without the protection of the field? Would it stay in high speed motion until interacted upon by something else (meteoroids/dust/gravitational fields)? Or would it disintegrate under this kind of speed?
Disintegrate or just stop and drop out of warp just like the ship does when they disengage warp normally. The ship doesn’t travel faster than the speed of light. It just warps space around the ship. That’s why they don’t have relativistic speeds like the warping of time like time dilation on the ship doesn’t happen.