Answer to: Will not turn onActually Jackson, while i hope you mean well, if you're not getting any power, then the computer hasn't even passed the POST (Power-On-Self-Test). As such, no amount of gentle hitting will fix it. If the computer is running on only battery power, then possibly such an impact could re-seat the battery, but i wouldn't be comfortable recommending that.
Answer to: Power Supply No Longer Working.I'm inclined to agree with Mayer. Unless there was liquid spillage, the magsafe board almost never fails. The down side is, if there was liquid spillage, a new magsafe will fix the problem... for all of 5 minutes. Then you'll need both a new logic board and magsafe board.
Answer to: Will not turn onSimple first - try removing the power and battery. Press the power button for 3 seconds (shouldn't do anything). Then replace the battery and power. If it starts up, you're good! If not... Try removing the RAM (under the keyboard), and see if it gives you three beeps on startup. If so, try starting with only one stick of RAM, may just be failing due to RAM that's no longer any good. If you don't hear three beeps (or anything) on startup with/without the RAM... probably a bad logic board.