dang extension cord

[dumars]

ext. cord fell and nudged the power cord near my psu. comp shuts down and i thought it just knocked it loose. comp wont turn on even though ive tried reinserting it/diff outlets/diff cord. a friends lendin me his extra psu soon to try out. any idea on how exactly a little nudge can cause this much trouble?
and what if the other psu doesnt work? means a fried mobo right?