Projectile Motion Video Lab Analysis

Graph of x-position vs. time (including best fit lines)

Equations for x-position vs. time

y = 2.286(m/s) x - 0.981(m/s)
For about 1.5 seconds, the slope is 2.286. This slope remains until the second bounce of the ball.  The new equation is y = 1.137(m/s) x + 0.712(m/s).  The reason why the slope dropped after hitting the floor was because gravity doesn't allow the ball to bounce quite as high as the previous bounce.

Description of the Horizontal Motion

This graph's horizontal velocity is constant, meaning it has no acceleration.  That is why the line is linear. For this experiment, we are ignoring air resistance.  The horizontal motion changes after the ball bounces because of the momentum shift.

Graph of y-position vs. time (including best fit lines)

Describe the Vertical Component of the Position of the Projectile

The vertical component is not linear, mainly because of gravity.  The component is both negative and positive at certain points.

Graph of y-velocity vs. time (including best fit line)

What can you say about the rate of change of the y-velocity as a function of time? How does the value of the slope of the linear fits compare to the acceleration of a freely falling object?

Rate of change is slope.  If our slope was steeper, it would have fell at the rate of gravity (-9.8 m/s/s) instead of -10.56 m/s/s.  Acceleration increases as the slope increases.

Explain the differences in the horizontal and vertical components of the motion of the projectile in terms of the force(s) acting on it after it was launched.

Horizontally, the components experienced no acceleration.  Horizontally the velocity did not change, it was constant throughout the video.  The only force it had horizontally was the force from the thrower, gravity, and air pressure.  Gravity created acceleration for the vertical component.  The force for the basketball came from gravity.  Once the ball passed it's origin (the throwers hands) on the way down, it's velocity increases.