PASCO ME-6831 Ballistic Pendulum_Projectile Launcher - Manual (Page 16)

P r o j e c t i l e L a u n c h e r E x p . 1 : P r o j e c t i l e M o t i o n
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12 012-05375C
2. Adjust the angle of the Projectile Launcher to zero degrees so the ball will by launched horizontally.
Part A: Determining the Initial Horizontal Speed of the Ball
1. Put a plastic ball in the Projectile Launcher and use the ramrod to cock it at the long range position. Fire one
shot to locate where the ball hits the floor. At that point, tape a piece of white paper to the floor. Place a piece
of carbon paper (carbon-side down) on top of the white paper and tape it in place.
• When the ball hits the carbon paper on the floor, it will leave a mark on the white paper.
2. Fire ten shots.
3. Measure the vertical distance from the bottom of the ball as it leaves the barrel to the
floor. Record this distance in the Data Table.
• The “Launch Position of Ball” in the barrel is marked on the label on the side of the
Launcher.
4. Use a plumb bob to find the point on the floor that is directly beneath the release point
on the barrel. Measure the horizontal distance along the floor from the release point to
the leading edge of the piece of white paper. Record the distance in the Data Table.
5. Carefully remove the carbon paper and measure from the leading edge of the white
paper to each of the ten dots. Record these distances in the Data Table and find the aver-
age. Calculate and record the total horizontal distance (distance to paper plus average distance from edge of
paper to dots).
6. Using the vertical distance, y, and the total horizontal distance, x, calculate the time of flight, t, and the initial
horizontal speed of the ball, v
0
. Record the time and speed in the Data Table.
Part B: Predicting the Range of a Ball Shot at an Angle
1. Adjust the angle of the Projectile Launcher to an angle between 30 and 60 degrees. Record this angle in the
second Data Table.
2. Using the initial speed and vertical distance from the first part of this experiment, calculate the new time of
flight and the new horizontal distance based on the assumption that the ball is shot at the new angle you have
just selected. Record the predictions in the second Data Table.
3. Draw a line across the middle of a white piece of paper and tape the paper on the floor so that the line on the
paper is at the predicted horizontal distance from the Projectile Launcher. Cover the white paper with carbon
paper (carbon side down) and tape the carbon paper in place.
4. Shoot the ball ten times.
5. Carefully remove the carbon paper. Measure the distances to the ten dots and record the distances in the sec-
ond Data Table.
Analysis
1. Calculate the percent difference between the predicted theoretical distance (“A”) and the actual average dis-
tance (“B”) when shot at an angle.
2. Estimate the precision of the predicted range. How many of the final 10 shots landed within this range?
Bottom
of ball
A B –
A B +
2
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