screen is blank
ipad was dropped, sceen is dark
iPad
You may have damaged the hardware and if you did, you will have to take it to an Apple Store or an authorized repair center to see of they can fix it.
in the meantime, try a reset first.
Reset the iPad by holding down on the sleep and home buttons at the same time for about 10-15 seconds until the Apple Logo appears - ignore the red slider if it appears on the screen - let go of the buttons. Let the iPad start up.