text: physics question....? a waiter in the dining car of a smoothly riding train pours a glass of water for a passenger. how would his task be affected if the velocity of the train is zero, if the velocity is nonzero but constant, and if the train is accelerating? this depends on the waiters experience... if he's real good, nothing will happen in any of the scenarios you brought up... if he's not, feel sorry for the customer as he gets drenched by the inexperienced and clumsy waiter!!!