Macbook Pro went black. It charges, but it won't turn on.

[joshdc75]

While being used, the Macbook went black. The charger shows a green light, but it won't power on at all.

Before this happened, a piece of the charger broke off and was stuck in the socket. It would work, but would spark every time it was connected again. I'm not sure if that's related...

 

[jojesa]

I suggest not using a charger that would spark with any electronic device.
A short circuit could kill the main board inside your MBP or it could spark a fire.
There is some power protection built in a MBP and if it still alive, it could be reset.
Make sure power cord is not connected.
Disconnect the battery (do not use any metal tools to disconect the battery).press the power Press the power button a couple times holding it for 10 - 15 seconds.
Connect the battery back, then connect the laptop charger (a good charger).