Vertical Motion of a
Obj: Examine Vy, dy motion of Projectile Motion
Materials: Launcher, metal and plastic balls, meter stick
and Analysis (let g = 10 m/s2)
1. Using the plumb line, be sure the launcher is
exactly perpendicular to the surface.
2. Place a ball (plastic or metal) in the launcher and plunge it down the designated number of clicks.
3. Fire a test round and estimate the maximum height of the ball.
4. Now, launch the ball for three trials on the same setting, recording the approximate height to within ±2cm.
5. Repeat for another ball (plastic or metal).
6. For each ball, determine the average maximum height, then calculate:
a. time to reach the maximum height.
b. initial Vy velocity
c. acceleration of gravity at the top of the flight.
d. total time in the air.
e. total distance traveled.
f. total displacement of the ball.
g. velocity of the ball after ¼ the total time of flight
7. On graph paper, accurately plot the velocity-time graph for the total time of flight of each ball using +vy as up and -vy as down. What does the slope represent? the total area?
8. Sketch a displacement vs time graph for the total time of flight for each ball.
9. Set the launcher on a table such that it is horizontal to the surface. Verify the launch velocity for each ball using the equations for vertical fall and the dx the ball travels after launch.
10. Which velocity is constant, vx or vy?
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