Projectile Motion Simulation: Firing Cannon http://phet.colorado.edu/en/simulation/projectile-motion
Exercise #1: Air Resistance
Factors to change: mass, size, initial speed
Factors to keep constant: Initial angle, initial height, distance to the bull’s eye
Set up a data table as shown below. Try “user defined” and also some preset objects. For each case compare the trajectory with and without air resistance:
Trial
#
Air
Resistance
(ON/OFF)
1
2
ON
OFF
Questions:
Initial Speed
(m/s)
Mass (kg) Diameter
(m)
Path different?
(Y/N)
1.
As the mass of a projectile increases, does the trajectory with air resistance get closer to or further from the trajectory ignoring air resistance?
2.
As the initial speed of the projectile increases, does the trajectory with air resistance get closer to or further from the trajectory ignoring air resistance?
3.
As the size of the projectile increases, does the trajectory with air resistance get closer to or further from the trajectory ignoring air resistance?
Write a summary answering the original question: Under what circumstances can air resistance be ignored?
Projectile Motion Simulation: Firing Cannon http://phet.colorado.edu/en/simulation/projectile-motion
Exercise #2: Horizontally launched Projectiles
Click air resistance off. Click and drag the wheel of the cannon to the cannon 19.62 m above the ground. Use the tape measure!
Factors to change: initial speed
Factors to keep constant: air drag OFF, the initial angle at 0, initial height = 19.62 m
Set up a data table as shown below.
Trial
#
Initial
Speed
(m/s)
1
2
Questions:
Range (m) Time (s)
1.
How does the initial speed of a projectile launched horizontally affect the range of the projectile?
2.
How does the initial speed of a projectile launched horizontally affect the time of flight of the projectile?
3.
Write the mathematical relationship between the range and the horizontal launch speed of a projectile.
Write a summary answering the original question: What factors affect range of a horizontally fired projectile and the time the projectile is in the air

Projectile Motion Simulation: Firing Cannon http://phet.colorado.edu/en/simulation/projectile-motion
Exercise #3: Projectiles Launched at Angles
Factors to change: initial angle: 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90
Factors to keep constant: air resistance off, initial speed = 15 m/s, cannon back at the ground level
Set up a data table as shown below.
Trial
#
1
Initial Speed
(m/s)
15
2 15
Questions:
Initial Angle
(degrees)
5
10
Range
(m)
Maximum height (m)
Time
(seconds)
1.
At what angle should a projectile be launched to achieve a maximum range?
2.
In the data table, certain launch angles result in the same range. Write these angles side by side. What is the relationship between these angles?
3.
At what angle should a projectile be launched to achieve a maximum height?
4.
How is the time spent in the air affected by the launch angle?
Write a summary answering the original question: How does the launch angle affect the flight of a projectile?