Wont turn on

[wardridge]

I put my mac to sleep with about 30% power and when I got home and went to charge it, it wouldnt come on. I popped the batter out and put it back in, nothing, no engine revving. The charging light on the front is on and steady (not pulsing). And the charge level button the on the back where battery is shows around 30%? What is up? It wont do anything