Tablet do not turn on

My samsung galaxi tab 4 just froze on a game i played. Tried to turn tab off but nothing happened. I put the tab aside and check on it again after an hour. The tablet sreen was off so I tried to turn tab on again but sreen did not light up. I put the tab on charge for an hour but the battery sign did not come on. The tab is left on charger for an hour an try to turn tab on again,still not rurn on.