Describe the motion of an object that is initially traveling with a constant velocity and then receives an acceleration of constant magnitude a) in a direction parallel to the initial velocity, b) in a direction perpendicular to the initial velocity, and c) that is always perpendicular to the instantaneous velocity or direction of motion. a) Same direction, and would speed up b) Object would slow down - Something is going forward and has a instantaneous acceleration against it, it would seem to slow down? c) Object would stop - If something is constantly pressing down on something going forward, it cannot have forward motion, if the magnitude of both are the same. But then again this does not make sense with gravity. I drew a picture, but with arrows. Here is what my book says, "If an object is initially moving with a constant velocity and suddenly experiences an acceleration in the direction of the velocity or opposite to it, it will continue in a straight line path, either speeding up or slowing down, respectively." Am I way off? Do you mind explaining this to me?