Raj says he won a radio contest by calling in with the station's motto in Hindi. But Raj doesn't know Hindi, he says so in another episode...

Also, Kripke's prank didn't damage any university equipment. But Sheldon's did. And could have caused problems for the people the stuff fell on, even if it had been just Kripke.

Raj also uses Hindi in S03E12 The Psychic Vortex, despite not knowing the language.