My Ipad does not start even after charging for whole day. it shows black screen.

[iMore Question]

It got switched off so i charged it before going to office.

 

[G.4]

You should take it to the nearest Apple Store. Make an appointment at the Genius Bar in advance and you won't have to be there as long. If they can't fix it, depending on how old it is, they may just give you a new one.