Multiple choice general knowledge science & technology An object following a straight-line path at a constant speed must be having: zero acceleration no force acting upon it a net force acting on it in the direction of motion None of the above Reveal answer Fill a bubble to check yourself A Correct answer Explanation For an object moving in a straight line at constant speed, both the magnitude and direction of velocity remain unchanged. Acceleration is the rate of change of velocity, so zero change means zero acceleration.