Lesson 1: Forces

Lesson 2: Energy

Challenge - Basketball and the Hierarchy

In this tutorial, you will learn about how forces interact to produce projectile motion of a cannonball as it is launched from a catapult. You will begin by opening the Unity editor and downloading the project assets by following the included link. When you have the assets loaded and configured, you will start lesson one and begin working through the included steps. By changing the sliders that control your cannonball’s mass and the spring force of your catapult, you will watch how the forces applied by a catapult affect the arc and speed of a projectile. Using the data set you collect from the launch; you will calculate the acceleration of your cannonball. Once you are finished with the lesson activity, you will move on to the target free play section and experiment with mass and force until you are able to hit the center of a target.   

You will be able to explain the relationship between the forces applied to a cannonball, the mass of the ball, and the ball’s acceleration. Using what you've learned, you will find the optimal mass and force settings needed to hit the bullseye on a target. 

By the end of this lesson, you will be able to:

Adjust the mass of the cannonball being launched from a catapult.

Adjust the force applied to a cannonball by a catapult.

Understand the relationship between a force applied to a cannonball and its velocity.

Understand the relationship between a force applied to a cannonball and the distance it travels.

Use the velocity calculated in the Unity editor to determine the acceleration of a cannonball at different points in its arc.

*Note:  Follow along in the worksheet that can be found under Tutorial Materials. This is also where you can find other important resources like the Formulas and More page. 

Lesson 1.pdf

Worksheet.pdf

Formulas and More.pdf

CatapultPhysics .unitypackage.zip

Overview

Before you begin

Download the asset package

Experiment with force variables

Calculate the cannonball's acceleration

Open Target Free Play and Use Variable Forces to Hit the Target

CatapultPhysics.zip

Download the Asset Package

Select Lesson 1 and Experiment with Force Variables 

Calculate your cannonball's acceleration

Open Target Free Play and Use Variable Forces to Hit the Target 

Use the skills you’ve learned in the previous two lessons to score on a basketball hoop. After you’ve scored, you will have to use the hierarchy and inspector windows to manipulate the way your catapult works. When you’ve found out how to make changes to your catapult, try the Free Play activities again using different catapult settings. When you’ve finished working with the catapult settings, look at the code that calculates the values you see inside the simulation.

Catapult will throw a cannonball through a basketball hoop

Catapult settings and characteristics will be manipulated

In this challenge, you will reinforce the following skills/concepts:

Using mass and force sliders to send a cannonball to a specific location

Use the hierarchy menu to select elements of your catapult

Adjust the launch settings of your catapult using the inspector window in Unity

Complete the Free Play activities without the use of the force and mass sliders

Adjust the project settings and investigate the effect of your changes in the Free Play activities

Look at the code that allows the physics editor to make calculations

Challenge.pdf

Quiz.pdf

Score a basket

Adjust the trajectory without the sliders

More things to try

The catapult simulation has set variables

The catapult launches at a 45-degree angle

The catapult and cannonball have predetermined settings

The simulation also has set time and gravity values

The simulation is built with code

Curriculum Connections.pdf

Lesson 2.pdf

Quiz Answer Guide.pdf

Worksheet Answer Guide.pdf

This project allows students to experiment with foundational Physics concepts like mass, velocity, forces, and energy within Unity, a powerful real-time physics engine. This provides students with a fun and interactive way to tinker with various physical constants and immediately see their impact in a simulated environment. Not only is this an excellent way for students to solidify their understanding of these concepts, but it will also open their eyes to the possibility of using 3D engines like Unity to grapple with real-world scenarios.

In this project, you will have a chance to explore the physics involved in a catapult launch. Lessons on forces and energy will guide your exploration and a final challenge will test your knowledge. You will be manipulating multiple variables in the engine itself to produce changes in velocity, acceleration, distance and more!

This project is powered by Enable Education. You can find a link to the Enable Education website in the Project Materials to the right.

2022.3

2018.3

Catapult Physics; Forces, and Energy

0599d364-706d-52a8-a748-2c08f767bd57:7J5jNyJEljLpdsdJk8NCWb

See attached file labelled "Curriculum Connections.pdf"

See attached file labelled "Lesson 1.pdf"

 Use the velocity calculated in the Unity editor to determine the acceleration of a cannonball at different points in its arc.

Note: Use the equations provided in the Formulas and More page to help you calculate the acceleration of your cannonball.

The player will be able to explain the relationship between the forces applied to a cannonball, the mass of the ball, and the ball’s acceleration. Using what they’ve learned, they will find the optimal mass and force settings needed to hit the bullseye on a target.

At the end of this project, you will be able to:

Understand the relationship between a force applied to a cannonball and the distance it travels. 

Adjust the mass of a cannonball and the force being used to launch it and understand the relationship between mass, force, and energy. 

Understand the relationship between elastic potential energy and kinetic energy.

Understand the relationship between the kinetic energy involved in the launch of a cannonball and the gravitational potential energy that a cannonball gains as it travels higher.

Explain the relationship between the law of conservation of energy and the way a catapult launches a cannonball.

Use kinematic equations to find the acceleration of a ball as it launches from a catapult.  

If you’re new to Unity, welcome! The Unity Essentials learning pathway has been designed to help you get set up and ready to create in the Unity Editor. We recommend you complete this pathway before continuing with the Catapult Physics; Forces, and Energy tutorial.

Before you begin to set up your Unity project, consider updating your Unity Hub to the latest release. If you are using an older version of the Hub, there may be differences between the guidance provided and your experience.

If you need to refresh your memory of the Unity Editor basics, you can take a moment to review Explore the Unity Editor at any time. 

In this step, you'll open the Unity Editor and configure it so that you can start the lessons!

1.  Scroll up to the Overview section of this page, locate the Tutorial Materials and select the link labeled CatapultPhysics.zip. Download the file and save it somewhere where it will be easy to find.

2.  Extract all the files from the zip package to a location of your choice.

4.  In the Unity Hub, create a new project using the 3D Core template. If you are not familiar with this process, you can review the Project setup processes tutorial.

Your Unity project may take a few minutes to open.

5.   When the project opens, from the main menu, select Assets >Import Package > Custom Package. 

6.  Browse your computer for the unzipped file, select it, and select Open.

7.  Make sure everything is selected in the Import Unity Package window, then select Import.

8.  In your Project folder, go to Assets > Scenes and double-click the PhysicsCatapult scene to open it.

9. You should now see a catapult. If you don´t see the catapult in the centre of the scene window, select the Catapult GameObject in the Hierarchy and press F on your keyboard. 

10.  From the main menu, select Window > Physics Config Window.

11. Click and drag the EditorPhysicsConfig tab to the rightmost side of the screen and dock it. 

Image showing the link to the CatapultPhysics.zip file under the Materials section.

The EditorPhysicsConfig window docked next to the Inspector and Lighting windows.

Before the tension is released and the cannonball is launched, the cannonball remains stationary because the mass of the cannonball and the tension holding it down cancel out the force being applied by the catapult’s spring.

There are complex forces acting on the cannonball as it goes from its resting position to the position at launch. The force the spoon is exerting on the cannonball that keeps it from flying outwards is called centripetal force. The force that the cannonball exerts on the spoon that pushes away from the center as it is being launched is called centrifugal force.

In this section, you’ll experiment with different force variables to see the impact of the changes on the ball's trajectory:

4.  Using the two available sliders, change the settings to two random numbers. 

5.  Select Proceed to Step 2 to see how the selections you made using the mass and force slider affect the way your cannonball is launched.

6.  Select Proceed to Step 3 and record the velocity of the cannonball at the apex of its arc.

The EditorPhysicsConfig window showing Lesson 1 selected.

 Screenshot of the Cannonball Mass and Spring Force sliders.

In this section, you will use data from the simulation to calculate the acceleration of the cannonball.

To calculate acceleration, you must gather a few data points and use a basic physics formula. The formula you'll need is F=ma, but a reference sheet with all the required information is provided: 

1.  Download the Formulas and More reference sheet from the Tutorial Materials section at the top of this tutorial.

2.  Download the worksheet also listed under the Tutorial Materials and follow along on the worksheet as you continue through the lessons.

4.  Select the Lesson 1 [Forces] button and pick a setting for your mass and spring force. 

5.  Proceed through the three steps as before and take note of the velocity of the cannonball again.

6.  Using the velocity data points you’ve recorded and the provided reference sheet, calculate the acceleration of the cannonball from prelaunch to the apex of its arc.

7.  Using the velocity data points you’ve recorded and the provided reference sheet, calculate the acceleration of the cannonball from the apex of its arc to when it settles on the ground.

8.  In the worksheet, calculate the cannonball's acceleration after it’s launched using the resultant force and the mass you've selected with the sliders.

Teacher Tip: The only force acting on the cannonball at this point is gravity.

 Screenshots of the available materials for download.

Screenshot showing the velocity and weight of the cannonball mid-flight.

In this section, you will use what you have learned to hit a given target with the cannonball:

2.  Select the Free Play [Target] button. A wall with a target is now presented to you.

3.  Try to hit each of the colored rings on the target by changing the mass of the cannonball and the catapult’s spring force, starting with the black ring.

4.  Once you’ve hit each of the colored rings on the target, try and hit the bullseye at the target’s center.

5.  Once you’ve found a set of mass and spring force values that allow you to hit the center of the target, find a way to hit the center of the target with the mass set to its lowest and highest values.

In this lesson, you learned about the impact of mass and force on the trajectory of a projectile. You also learned how to calculate the acceleration of a projectile with given data points.

In the next section, you'll learn about the different types of energy involved in the motion of an object.

Lesson 1: Forces

1. Overview

2. Before you begin

3. Download the asset package

4. Experiment with force variables

5. Calculate the cannonball's acceleration

6. Open Target Free Play and Use Variable Forces to Hit the Target

Complete this tutorial