You're going to need to post more info than that for anyone to help.
What model is the computer? Tower, iMac, desktop, lap top? Be specific. G3 G4 G5? Speed?
You turned on the TV, and the computer shut down ten seconds later. Did the TV shut down too?
Does the computer do anything? Lights, fans, sounds, smoke?
Lampie
I have had this Mac for about 2 years and it has never had any problems. But just today it cut off for no reason and won't turn back on. Noone was really using it but there was music playing, that is about it. The computer is plugged into the wall and that is usually the only thing plugged into that particular outlet. Sometimes a small extension cord is used for the tv, but we've had the tv and the mac on and have never had a problem. In this instance, I plugged in the cord for the tv and turned it on to make sure it worked, it was on for about 10 seconds and the mac just turned off. I'm not sure if that had anything to do with why it turned off or not, but I tried unplugging it and it won't come back on. I tried holding down on the power button and nothing happened. Any help would be great please!!!! Its a MacOS X

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