Using Projectiles

Today's Goal

• Predict how varying initial conditions affect a projectile path.
• Use reasoning to explain the predictions.
• Explain projectile motion terms in their own words.
• Describe why using the simulation is a good method for studying projectiles.

Use this simulation to help answer the following questions.  For each problem you solve, you must include 

1. a sketch
2. the project chart (all 15 variables) for any problem marked with a **
3. any assumptions you had to make
4. all data you measured from the simulation marked in a colored pencil
5. all data you calculated marked with pencil and work shown.

The project chart

projectile sim


  1. One day after school, you pick up a cracked golf ball in the back yard. You decide to throw it in the trash can with an initial velocity of 3 m/s. What affects whether or not it gets in the can?  **

2. The Projectile Motion sim allows several variables that can change: you can change the height of the cannon, the location of the cannon, its angle, etc. A tape measure is present to help you measure heights and distances. Use the sim to test your ideas about the things that affect the landing spot of a projectile. 

Make a complete list of things that affect the landing site of a projectile

Next to each item, briefly explain why you think the landing location changes.
Compare your list with another group, discuss your explanations and make modifications.

3. Use the simulation to investigate how the different objects in the simulation affect the shape of the flight path. Summarize your discoveries by including examples with friction and without in the explanations for  different flight paths.

4. Launch an object from the cannon at a 30 degree angle and make it hit the target. List the angle, initial speed, and mass of the object before you start.   Resolve the initial speed into an x-speed and a y-speed using a vector diagram.  Why do these speeds change over time? **

5. 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, you draw a picture of a projectile path and label all the terms that are on the simulation page. Draw a picture like you would for your friend and write what you would tell her about the terms. 

6. Make a perfect parabola projectile with the cannon.   Measure d(x) and d(y) down (careful, the distance tool may not work well here), and fill out the project chart, assuming that gravity is -9.8 m/s/s.


7.  Throw a set of car keys or pencil into the air and watch it land.   Clearly identify the error sources the simulation eliminates or minimizes, compared to launching projectiles yourself and studying the actual flight path and landing spot.

8.  Make a chart that goes up by 10 degrees each time, starting with 0 degrees and ending with 90 degrees.  Mark the distance in meters traveled for each time.  Now, make a x-y graph of the angle vs. distance, where angle is the x-variable.

9.  Hand in.