Problem with N5110 - power cord light goes off

I have a Dell N5110 laptop.

My Hard drive crashed a couple of weeks ago and I replaced it.

The system was working fine for a couple of days until while turning on today, a little smoke came out of the machine.

When I tried to turn it on again, it does not turn on and the lighted rim of the AC power cord i.e the light that is around the connector end of the cord, goes off!!!

I am at a loss as to why this would happen. Is there something wrong with my power jack? Or is it some kind of reverse voltage? I am not too sure.

If someone could please explain why this is happening and the resolution, it'd be a big help.

Thank you

Rohit