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

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Experiment with force and mass

Document how the law of conservation of energy applies to a projectile.

Use a kinematic equation to find the acceleration of the cannonball

Knock down the boxes

In this tutorial, you will learn about the relationship between mass, force, and energy as you calculate the velocity and acceleration of the cannonball on your worksheet. You will begin by opening lesson two and looking at how the mass and force sliders you used in the last lesson affect the energy involved in a catapult launching a projectile. When you’ve used your sliders to change the energy being used in your catapult, you will launch the ball and track the energy associated with the ball through its arc between the catapult and the ground. Using the law of conservation of energy, you will explain how energy is used and transferred by the catapult. Using one of the kinematic equations, you will be calculating the acceleration of your cannonball for two different sets of mass and force values. When you have finished with the lesson, you will move on to the boxes free play activity and track the energy needed to knock down all the boxes.    

You will be able to explain the relationship between mass, force, potential energy, and kinetic energy. You will use kinematic equations to find the acceleration of a cannonball launched from a catapult. Using what you've learned, you will find the optimal mass, force, and energy needed to knock down a stack of blocks. 

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

*Note: The law of conservation of energy and the kinematic equations can be found in the Formulas and More document.

See attached file labelled "Curriculum Connections.pdf"

 See attached file labelled "Lesson 2.pdf" 

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 the kinetic energy involved in the launch of a cannonball and the gravitational potential energy that a cannon ball gains as it travels higher.

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

The player will be able to explain the relationship between mass, force, potential energy, and kinetic energy. Players will use kinematic equations to find the acceleration of a cannonball launched from a catapult. Using what they’ve learned, they will find the optimal mass, force, and energy needed to knock down a stack of blocks.

Note: The law of conservation of energy and the kinematic equations can be found in the Formulas and More document.

In this tutorial you’ll change the force applied to the cannonball by the catapult and change the mass of the cannonball itself. You’ll learn how different forces interact with one another to change the trajectory of the cannonball and learn how to calculate the velocity of the cannonball depending on the values of the forces applied to it. Then, you’ll use your new knowledge to find the most effective way to knock down a stack of boxes with the cannonball! 

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

Use the Cannonball Mass and Spring Force sliders to adjust the energy used by your catapult:

2.  Select the Lesson 2 [Energy] button and then the Proceed to Step 1 button.

3.  Use the two available sliders to configure the mass and force settings of your catapult and observe how the elastic and gravitational energy values change.

4.  After setting some values with the sliders, select the Proceed to Step 2 button and observe how gravitational potential energy changes as the arm on your catapult rises.

5.  Select the Proceed to Step 3 button and observe the energy involved in launching your catapult.

6.  Select the Continue button and observe how the gravitational potential energy changes as the cannonball progresses through its arc.

 Image showing the velocity of, and gravity acting on, the cannonball mid-flight.

In this section, you will repeat the steps from the previous section, but you will document your findings in the provided worksheet.

1.  Enter Play mode and select the Lesson 2 [Energy] button.

2.  Proceed through the steps with your own value settings like you did before. 

We encourage you to try it a few times with different values. Pay attention to the energy values as the arm starts moving and note the difference between the elastic energy being used to lift the arm and the kinetic energy that is put into the cannonball.

3.  Work your way through the steps again, but this time fill out the Lesson 2: Energy section of your worksheet and explain how the law of conservation of energy applies to the energy values through the launch of your ball.

Teacher Tip: The law of conservation of energy is outlined in the Formulas and More page. Record your answer on your worksheet.

In this step, you will use the available information to calculate velocity and acceleration:

1.  Enter Play mode and pick values for your cannonball mass and spring force as before.

2.  Run the simulation and, in your worksheet, record the distance the cannonball travels and the velocity at the top of its arc in your worksheet.

3.  Using the initial velocity you recorded and the gravitational constant, calculate the velocity of the cannonball at the top of its arc.

4.  Using the distance and velocity you recorded and the kinematic equation, calculate the acceleration of the cannonball from the top of its arc to the ground.

5.  Repeat the process one more time, this time using a different set of values for the cannonball’s mass and the catapult’s spring force.

Tip: The kinematic equations are listed in the Formulas and More page. Pick the one that allows you to find acceleration based on the time, initial velocity, and velocity at the top of the cannonball’s arc.

Screenshot showing the impact of Gravity, the elasticity and the kinetic energy of the launch.

Screenshot showing the cannonball in flight and the various forces acting on it.

In this section, you will use what you have learned to knock down a stack of boxes with the cannonball:

1.  Enter Play mode and select the Free Play [Boxes] button.

2.  Experiment with different values to find the settings that will allow you to knock down all the boxes.

Find a way to knock down all 12 boxes with the lowest possible cannonball mass. Once you’ve done that, find a way to knock down all 12 boxes with the lowest possible spring force.

Lesson 2: Energy

1. Overview

2. Experiment with force and mass

3. Document how the law of conservation of energy applies to a projectile.

4. Use a kinematic equation to find the acceleration of the cannonball

5. Knock down the boxes

Complete this tutorial