# Modeling the Motion of a Projectile Purpose In this lab you are going to analyz

Modeling the Motion of a Projectile

Purpose

In this lab you are going to analyze in groups various scenarios of the movement of a projectile using

Spreadsheets. The goal of this assignment is to understand how to use Spreadsheets to model physical

behavior and to read graphs and explain what insight it provides in the movement. You will understand how

varying the conditions affected the motion of projectile. Many careers in STEM use computational modeling

techniques to develop their designs, this lab is designed to introduce these skills.

Task

• Read through the procedure and watch the videos. Meet with your group and discuss what questions

or interests you have. Figure out what object you are interested in modeling their behavior and the

importance for the modeling of the behavior

• Assign tasks to group members or decide to work together on each step.

• Code the spreadsheet and analyze the behavior. Check to see if there are errors in the analysis, does it

make logical sense? If it appears wrong, double check. Hint: choose variables that will stay consistent

throughout the study for proper comparison like initial position.

• Write the report. Every group member reads the report to edit before submission.

PROCEDURE

A video has been made to show how to use a spreadsheet to model projectile motion. Your goal is to analyze

different conditions and the result. Your group will write a report explaining the results you have found with

graphs that are labeled. This project may take some time as you do it. If you wish to use a different

programing software or language like Matlab (or Octave), python, C++ etc, you may do so but graphs and the

file you used to analyze the motion are required to be submitted. (I have a basic understanding of many of

these codes to be able to get the jist of what you are doing.)

STEPS

Keep the height the same in all these steps in order to compare the information. Choose a spherical object like

a basketball, baseball, etc.

First step: Model a projectile motion with an initial velocity in the horizontal direction.

Second step: Model a projectile motion with a different initial velocity in the horizontal direction. What

changed?

Third step: Model a projectile motion with an initial velocity at varying angles. (Example: 15, 30, 45, 60, 75

degrees) Notice what changed. What happened to the motion of the ball?

Fourth step: What happens if there is a constant force due to wind? In the opposite direction of gravity or

same direction of gravity? Now only in the x direction either against or with the motion? (Remember Newton’s

Second Law!)

Fifth step: What happens if the object is a different size? Or has a different mass?

Sixth step: What happens if there is a drag force? (This is a more complicated step as drag force is dependent

of velocity of the object with is changing.) Assume the drag coefficient is 0.5 (for sphere shape object). Do you

only have the drag force in one direction or both? Does changing the fluid impact the motion (ignore

buoyancy)?

Report Requirements

In the report you will hand in, you will need to:

One write-up per group.

o Should only receive two files:

▪ The write up in a .doc/.docx or .pdf file

▪ Your code or spreadsheet with your work.

• Explain the setup for your study. Are you particularly interested in something (like a movement of a

baseball flying in the air?)

• Explain what happens each time you varied a parameter, is it what you expect?

• Complete every step. Have a graph for every step, discuss how the parameter changed the outcome.

(you can have a comparison graph instead of one graph per change)

o In the third step try all the angles and see what happens to time and range.

o In the fourth->sixth steps, explore how changing the object affects the previous steps and how

adding a force affects the motion. (Constant force in step 4 and Drag force in step 6. Did the

object hit terminal velocity before it hit the ground? Drag force is more complicated and takes

more time to analyze.)

o Each study will be discussed with graphs to explain the motion: position vs time, x vs y, velocity

vs time, etc. Choose a couple at which to look. Overlay graphs from various steps to make

easier comparisons. (Hint when making comparisons, only have one variable be different, for

example: If changing initial velocity then make sure angle and initial position are the same.

Unless you are doing a gradual change comparison for example: v=10m/s horizontally, v=20m/s

horizontally, and v=20m/s at 60o all on one graph.)

• Graphs that are labeled and demonstrate what you have studied. Choose which one (or ones) best

describes what you are trying to compare and study. (Do not use velocity vs time for one step and then

jump to position vs time for another step.) What aspect of the motion is changing when you change a

parameter, and do you see it?

Types of graphs.

o Position vs time

o X vs Y

o Velocity vs time

o Overlay graphs from multiple steps example: Step 1 (horizontal only velocity) and Step

2(different horizontal velocity) or compare Step 1 with Step 3 with all the angles on one graph,

etc.

o Overlay graphs of different values in one step/change example , ay,vy,y vs time

o A 3-D graph if it is interesting example x,y,t graph