course Phy 201 A ball rolls off the end of an incline with a vertical velocity of 20 cm/s downward, and a horizontal velocity of 80 cm/s. The ball falls freely to the floor 120 cm below.For the interval between the end of the ramp and the floor, what are the ball's initial velocity, displacement and acceleration in the vertical direction? V0= 0 `ds= 120cm vAve = 20 cm/s + 0 /2 = 10 cm/s `dt = 120 cm/ 10 cm/s = 12 s A= 20 cm/ 12s = 1.67 cm/s^2 What therefore are its final velocity, displacement, change in velocity and average velocity in the vertical direction? Vf = 20 cm/s `ds = 120 cm `dv = 20 cm vAve = 10 cm/s What are the ball's acceleration and initial velocity in the horizontal direction, and what is the change in clock time, during this interval? V0= 0 Vf = 80 cm/s `ds = 120 cm `dt= 120cm/ 40 cm/s What therefore are its displacement, final velocity, average velocity and change in velocity in the horizontal direction during this interval? vAve = 40 cm/s `ds = 120 cm Vf = 80 cm/s `dv = 80 cm/s After the instant of impact with the floor, can we expect that the ball will be uniformly accelerated? No. After the ball makes contact with the floor it will no longer be uniformly accelerated because of the impact with the floor. Why does this analysis stop at the instant of impact with the floor? It stops at the instant of impact with the floor because the floor interrupts its path of uniformly accelerated motion. The abrupt interference stops the motion. "