A ball is rolling on a smooth horizontal floor towards the east. The positive x-axis is taken towards the east. The ball continues to move in the same direction but its speed decreases uniformly until it finally comes to rest.
Answer the following about the motion of the ball:
(i) State the direction of the ball’s velocity while it is still moving.
(ii) What is the direction of its acceleration during this motion? Give a reason for your answer.
(iii) Taking east as positive, assign algebraic signs (positive, negative or zero) to the velocity and the acceleration of the ball during the motion.
(iv) Will the acceleration in this case be called ‘retardation’? Explain your answer in one or two sentences.