You wake up in a windowless room on a train, traveling along particularly smooth, horizo...

You wake up in a windowless room on a train, traveling along particularly smooth, horizontal tracks. You don’t know in which direction the train is moving, but you are carrying a compass. You place a ball in the center of the floor and observe as it rolls east. If the train is moving west, is it speeding up, slowing down, or turning with constant speed? (If turning, state right or left.) What if it is moving east? Explain.