Think about the moon revolving around the earth. This is circular motion. Gravity provides the centripetal force that causes the moon's circular round the earth. The moon is accelerating towards the earth, but never gets any closer to the earth. Why?

i think its

  distance on the y-axis and time on the x-axis.

explanation:

the instantaneous velocity = change in position/time taken

the slope of the graph should give instantaneous velocity.

  slope of a graph = change in value of y -axis / change in values of x -axis

  comparing both the equations

    change in value of y -axis = change in position

  change in values of x -axis = time taken

so position values should be on the y axis and time values should be on the x axis.

distance on the y-axis and time on the x-axis.