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Sometimes crazy things Happened-so crazy, they don’t even look real. Last week, Philadelphia right forward Bryce Harper used some practice sticks to warm up before the game.He hit a nice line drive and then *It collided with another ball in mid-air*. This allows us to unravel some interesting physical processes. Let us look at the possibility of this event.

What data can we get from the video?

The crash involved two balls. Harper may have started flying at home runs. I call this ball A. The second ball was thrown at home plate by a player somewhere outfield. Let us call this ball B. I need to get a value to understand the starting position of the ball, its speed, and the location of the collision. The Major League Baseball clip I linked earlier is not the best video because it cannot show the complete track of any ball, so we may only need to approximate some content.

One thing we can see is the collision between the two balls, which occurred above the second base. After that, it seems that ball B descends straight and landed near the base. But how high is the impact point? By watching the video, you can get about the free fall time of the B ball. (According to my measurement, I will advance at 1.3 seconds.) If I know the time required to fall and the vertical acceleration is -9.8 meters squared per second (because this is happening on the earth), so I can Use the following kinematic equation to find the descent distance:

By estimating the falling time, I got a collision height of 8.3 meters. If the baseball field is on the xz plane, and the position above the ground is in the y direction, it means that I now have all three coordinates of the collision point: x, y, and z. I can use this to find the launch speed of ball A. I know it starts to move on the home plate, which is 127 feet from the second base point. Therefore, I put the origin back in place, and then let the x-axis follow the line between the origin and the second.

Now, I only need the initial velocity vector of ball A to pass through the collision point. There are several ways to find it, but the easiest way is to just use Python to draw the trajectory of the ball and adjust the launch angle until it “hits” the collision.I want to use Starting ball speed (Exit speed) is 100 miles per hour. (44.7 meters per second.)

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