Motion in one Dimension 5 - motion of downward

Now the initial velocity is not 0 m/s. The ball can get 2 kind of initial non-zero velocity. One is downward direction velocity and another is upward direction velocity.

Let's see in the first case. The situation for the ball was changed.

All situation is described on the Figure 5-1.

Figure5-1

Even the ball has initial velocity,the motion is one dimensional constant acceleration motion.

I will give you several problems for homework.

HW1) Find out the velocity when the ball reached the surface.

HW2) How long will it take to reach the surface from the top.

HW3) After 2 second, describe the displacement of the ball.

I hope you can solve them easily. When you meet troubles, review previous lectures. All solutions are there for this homework.

Good luck.

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