"Ти їси яблука?"

Yes, it is

yeah but it's the same in the nominative form of the plural.. яблуко is neuter and the accusative only differs from the nominative if the word is a) a living masculine one -а/-я b) a feminine one -у/-ю c) a living one in plural -ів/-їв/-/-ь an apple doesn't live so it stays the same