Contextualization

Introduction

Physics, like all sciences, has a central objective: to describe the world around us. An essential aspect of this world is motion. Whether it's the motion of planets around the sun, a car crossing the city, or a subatomic particle in a particle accelerator, mechanics is the area of physics that focuses on describing and understanding these movements.

Within mechanics, the study of collisions is a fundamental topic. A collision occurs when two or more bodies interact in such a way that there is a change in the direction or magnitude of their velocities. This topic is of vital importance to many areas of physics and is particularly relevant to classical physics.

In this project, we will focus on collisions in one dimension. This is a simplified but essential case to understand the nature of collisions and the laws that govern these events. Throughout this project, we will explore the concepts of momentum, energy, and conservation, which are at the core of these interactions.

Contextualization

Collisions are not only an important concept in physical theory but also have several practical applications in the real world. In safety engineering, for example, understanding the forces involved in a car collision can help design safer vehicles. In sports like billiards or bowling, the outcome of a game often depends on understanding the collisions between balls.

One can also think of more complex examples, such as studying the interaction of particles in a particle accelerator, which is also a form of collision. In this case, the laws of physics that govern these events may even provide clues about the fundamental building blocks of our universe.

Activity

Title: Collisions and Soapbox Cars

Project Objective

This project aims to investigate and understand the dynamics of collisions in one dimension through the construction and observation of soapbox cars.

Project Description

Groups will be invited to build two soapbox cars using simple materials and make them collide on a straight track, simulating a one-dimensional collision. Students will then analyze the collisions by noting the initial velocity of the cars, the angle of impact, and the velocity of the cars after the collision. They will then use these observations to calculate the linear momentum before and after the collision to verify the law of conservation of momentum.

Required Materials

1. Ball bearings
2. Wood for the car bases
3. Axles for the bearings
4. Screws to assemble the structure
5. Additional weight to adjust the mass of the cars (can be clay, lead, stones, etc.)
6. Tape measure or large ruler to measure distances
7. Stopwatch
8. Camera to record the collision (optional)

Step-by-Step Guide for the Activity

1. Divide students into groups of 3 to 5 people.
2. Each group will have to build two soapbox cars. There are numerous tutorials on the internet on how to do this. The cars should be robust enough to withstand multiple collisions.
3. Once the cars are ready, the groups must perform a total of five collisions documenting the initial velocity of the cars, the angle of impact (which should be as close to 180 degrees as possible), and the velocity of the cars after the collision.
4. With the collected data, students must calculate the linear momentum of the cars before and after the collision and verify the conservation of linear momentum.

Project Deliverables

Groups must submit a report in the format of an academic paper containing the following sections:

1. Introduction: In this section, students must contextualize the study of collisions in one dimension, its relevance and application in the real world, as well as the objective of this project.

2. Development: Here, the student must explain the theory behind collisions in one dimension, explain the activity in detail, indicate the methodology used, and finally present and discuss the results obtained. Photos and/or videos of the collisions, the data collected in each experiment, and the calculations performed to find the linear momentum should be included.

3. Conclusion: In this section, students must summarize the main points of their work, explain the lessons learned and the conclusions reached about the project. They can also discuss any problems encountered during the project execution and how they influenced the results.

4. Bibliography: Groups must indicate the sources they relied on to work on the project, such as books, web pages, videos, etc.

Students will learn how to conduct a real physical experiment, collect and analyze data, and apply theory to explain their results. Additionally, this project will develop socio-emotional skills such as time management, communication, and problem-solving in a team.