Projectile Motion Lab
Teacher’s Guide
Materials:
Projectile motion launcher
Projectile to be fired
Pie Pan (or other similarly sized, flat object)
Meter stick
General Idea:
The students are to fire a projectile horizontally and measure the horizontal distance traveled. From this, they can use
kinematics and v=dt to determine the original horizontal velocity of the projectile. Then using the same launcher and
projectile, they will rotate the launcher 300 and using kinematics and the idea of projectile motion, predict where the
projectile will land.
Time Frame:
One 45 minute class period for an AP level class. Two 45 minute class periods for an introductory level physics class.
Notes:
This lab is not designed as an introduction to projectile motion. I use this lab in my classroom as a final lab for the two
dimensional motion unit as some complex mathematics is involved.
In projectile motion, the motion is separated into the x and y directions. v = dt is the equation used in the x direction
since there is no acceleration. The y direction uses the kinematic equations.
For a horizontal launch, viy is always 0 and the acceleration is always 9.8 m/s2.
For a launch at an angle, the vertical motion must be split. You must consider the time and distance that the ball travels
up, then you must consider the time and distance that the ball travels down.
The launcher for our class, when set on a table, is exactly one meter tall and shoots an average distance of 2.8 m. These
numbers are used below to show what students’ work should look like and the calculations involved.
Example of Lab:
Projectile Motion Lab
Purpose: Determine the muzzle velocity of your projectile launcher. Then determine the location an object will land
when shot at an angle of 300 from your tabletop.
Procedure I:
1. Measure the vertical height (in meters) of a projectile that will be launched horizontally. Record in the table as d
in the y direction.
2. Shoot the projectile horizontally and measure the horizontal distance (in meters) that it travels. (You are looking
for where it first hits the ground). Repeat several times and find the average. Record in the table as d in the x
direction.
3. Fill in the initial vertical velocity and vertical acceleration for an object launched horizontally.
4. Solve for the horizontal velocity. Show all calculations.
Table and Calculations:
x
y
v=
vf =
d=
vi =
t=
a=
d=
t=
Procedure II:
1. Treat the velocity that you found in procedure 1 as the velocity for part 2 (since you will use the same launcher).
Determine the vx and vy components of the velocity for an object launched at 300. Record in the table as v in
the x direction and vi in the y direction.
2. Measure the height (in meters) at which the object will leave the launcher when rotated to 300. Record in the
table as d in the y direction.
3. Predict the location your object will land when launched from the table at an angle of 300. Show all calculations.
Table and Calculations:
x
y
v=
vf =
d=
vi =
t=
a=
d=
t=
Analysis:
Place a pie pan at the place where you think the object will land.
Shoot the marble.
If it lands in your pie pan your grade is a 10/10. For every 10 cm away it lands from the pie pan, 1 point will be deducted
from your grade. Good luck!
Your score = _________________/10