course Phy 202 Prelim. ObservationsKEx and KEy values change rapidly Ave time between collisons is about 1 second and ave speed of red ball is about 300 The blue ball is slower, requires more force to change movements, stops more easily, and I believe has a greater mass. The red ball turns yellow when it strikes another ball and recieves positive energy from the collison that is the velocity is increasing or otherwise said it is accelerating. I think the graphs represent the length of time the red and blue balls travel in one direction. I think it is a bar graph and each is bar is a time and distance."