SGC
Spot on - and it's not just 'at the end of the runway'. Thinking of the Spanair crash in Madrid where there was/is a ravine and a stream at the side of the runway. There was plenty of runway left but the ravine drop contributed to the breakup of the aircraft and the severity of the injuries (although paradoxically the water lessened burn severity).
Sunamer
Think of it in terms of a closed system in Newtownian mechanics and the conservation of momentum, rather than energy. If you could work out what speed the nosewheel was going, then I cant see how the speed of the aircraft at that point would be
less than that, although I agree that it is likely that it would be more.
