Projectile Lab Simulation—http://www.colorado.edu/physics/phet
Click on Simulations, then scroll to the bottom and click on Projectile Motion
1. One day after school, you are enjoying a soda in the back yard. When the can is empty, you decide to
throw it in the trashcan. What affects whether or not it gets in the can?
2. Open the Projectile Motion simulation. Play around with the various things you can change. A tape
measure is present to help you measure heights and distances. Use the simulation to test your ideas
about the things that affect the landing spot of a projectile. Below is a complete list of things that
you can change and things that can be measured by the simulation. Next to each item explain what it
is (for both things you can change and things you can measure) and how it affects the motion of the
projectile (just for things you can change).
Name of variable that Effect of the variable on the motion Describe the variable you can change of the projectile
Object The object that is launched No effect
The velocity of the projectile as it Increasing the initial velocity give the Initial velocity leaves the cannon projectile a greater range.
The angle that the cannon makes Angle of Cannon It effects both the height and the range with the horizontal
Mass The mass of the launched object No effect
Diameter The diameter of the launched object No effect
Whether the sim ignores or uses air Air resistance makes the object not go Air Resistance resistance as high nor as far
The higher the starting height is, the Height of the cannon The starting height of the cannon farther and higher the object will go
Name of quantity Describe what the measurement is measured by the sim
Range How far the object travels in the horizontal direction
Height Displacement of the object in the vertical direction
Time The time it takes for the object to land
3. Play around with the angle of the launch.
a. What angle yields the highest max height?
b. What angle yields the largest range?
c. Are there any angles that yield the same range? If so, what are they?
d. Are there any angles that yield the same range if you look at the zero displacement line (the
horizontal line at the level of where the projectile is lauched? What are they and what is their
relationship? (Only look at the projectile path to answer this, not the measurements given.)
4. Launch an object from the cannon. Turn air resistance off and keep it off for the rest of the sim. Fill
in the table below. You may have to use the tape measure to fill in some of the table.
Variable Value (include units) Measurement Value (include units)
Height (vertical Initial velocity displacement)
Angle of Cannon Time
Mass Max height
Height of the cannon
5. If you want the projectile to hit the target, what do you need the height (displacement) and range to
be? Find a combination of initial velocity and angle that hits the bull’s eye. Support with
calculations why it works. In other words, use the velocity, angle and vertical displacement to
calculate the range and show it matches the distance to the target. Show all work on your own
sheet of paper.
6. If I set the initial velocity at 15 m/s and the angle at 60;, use calculations to determine the following
things: max height, vertical displacement, time, and range. Show all work on your own sheet of
paper. Check your answers with the simulation (using tape measure when necessary), editing your
work if you were incorrect. (Don’t just change your answer, figure out what you did wrong!)
7. Suppose your friend asks you to tell them about projectiles. You start to explain, but she interrupts.
“Wait,” she says, “You’re using a lot of words I don’t understand. Can you explain in English?”
Knowing that a picture is worth a thousand words, draw a picture of a projectile path and label all the
key terms, including any necessary explanations. Do this on your own sheet of paper.
8. Change the initial height of the cannon (as measured from the crosshairs) to 7 meters (use the tape
measure). This way your height (vertical displacement) should be -7 m. Using the same initial
velocity and angle as in #6, calculate the max height (measured from the zero displacement line and
the ground), time, and range. Then check with the simulation, editing your calcs if necessary. Show
all work on your own sheet of paper.