Lesson Plan | Active Learning | Work: Constant Force

Assumptions: This Active Lesson Plan assumes: a 100-minute class, prior student study with both the Book and the start of Project development, and that only one activity (among the three suggested) will be chosen to be conducted during the class, as each activity is designed to take up a significant portion of the available time.

Objectives

Duration: (5 - 10 minutes)

The objectives stage aims to clearly establish what is expected for students to learn and be capable of by the end of the lesson. By defining the objectives, the teacher guides students on the competencies to be developed and ensures that both the prior preparation and classroom activities are aligned to achieve these goals. This allows for a targeted and effective approach during the flipped classroom, where classroom time is used for practice and in-depth discussions.

Main Objectives:

1. Equip students to understand and calculate the work done by a constant force, using the formula T = F * d * cosθ, where T is the work, F is the magnitude of the applied force, d is the distance traveled, and θ is the angle between the force and the displacement.

2. Develop practical application skills of work concepts in hypothetical and real situations, promoting logical reasoning and problem-solving.

Side Objectives:

1. Encourage critical analysis of the mathematical relationships involved in calculating work and its physical interpretation.

Introduction

Duration: (15 - 20 minutes)

This stage of the lesson plan aims to engage students and practically and contextually review the previously studied content on the work of a constant force. The problem situations encourage students to apply their knowledge in challenging scenarios, preparing them for practical activities in class. The contextualization, in turn, highlights the relevance of the theme in both real situations and practical applications, increasing interest and awareness of the importance of studying Physics.

Problem-Based Situations

1. Imagine an object weighing 10 kg is pulled by a constant force of 20 N, moving horizontally over 5 meters. What is the work done by the applied force?

2. Consider an elevator that lifts a mass of 500 kg at a constant speed of 2 m/s over a vertical distance of 10 meters. What is the work done by the elevator?

Contextualization

The concept of work is essential in many aspects of everyday life and in various fields of engineering and physics. For example, understanding the work of a constant force can help improve the design of machines that operate with linear or rotational motions. Moreover, in daily life, work is often used to measure the efficiency and usefulness of various activities. For example, pushing a shopping cart in a supermarket involves work to move the cart against friction and gravity, directly influencing the amount of energy used.

Development

Duration: (70 - 80 minutes)

The development stage is designed to allow students to practically and creatively apply the concepts of work of a constant force studied previously. By working in groups to solve specific challenges, students develop not only a deeper understanding of the concept but also teamwork, critical thinking, and problem-solving skills. Each proposed activity is structured to maximize student engagement and ensure meaningful learning through experimentation and direct application of theoretical concepts.

Activity Suggestions

It is recommended to carry out only one of the suggested activities

Activity 1 - Bridge Challenge

> Duration: (60 - 70 minutes)

- Objective: Apply the concept of work of a constant force in practice, promoting teamwork and creativity in solving simple engineering problems.

- Description: Students, divided into groups of up to 5 people, are challenged to design a small bridge out of ice cream sticks that can support the greatest possible weight. Each group receives a limited number of sticks and glue, and must apply the concept of work of a constant force to determine the optimal distribution of sticks to maximize the force supported.

- Instructions:

• Form groups of up to 5 people.

• Use the provided materials (ice cream sticks and glue) to build a bridge.

• Before starting construction, discuss and draw a plan that optimizes the distribution of sticks to support the maximum weight.

• Test the bridge's strength using progressively heavier weights.

• Record the maximum weight supported by the bridge and the stick distribution plan that proved to be most effective.

• Prepare a brief presentation explaining the work concept applied in building the bridge.

Activity 2 - Cart Race

> Duration: (60 - 70 minutes)

- Objective: Understand and apply the concept of work of a constant force in an engineering context, while promoting critical thinking and problem-solving skills.

- Description: In this challenge, students, in groups, build a small cart using recyclable materials such as milk cartons, popsicle sticks, and pulleys. The objective is to make the cart travel the greatest distance possible with the application of a constant force, represented by an elastic band that is stretched and releases energy for the movement of the cart.

- Instructions:

• Form groups of up to 5 people.

• Use recyclable materials to build a cart that can support an elastic band that will propel it forward.

• Stretch the elastic band and attach it to the cart so that when released, the cart moves forward.

• Mark a starting line and see which cart travels the greatest distance after the elastic is released.

• Calculate the work done by the elastic to propel the cart, considering the distance traveled.

• Discuss the differences in performance between the various cart designs and the impact of forces on the work done.

Activity 3 - Balloon Festival

> Duration: (60 - 70 minutes)

- Objective: Apply the concept of work of a constant force in a practical experiment and understand how variables affect the final result, promoting cooperation and analytical thinking.

- Description: Student groups use balloons, string, and small baskets to build a 'gondola' that can be raised by pulling the balloon down a corridor with the application of a constant force. The goal is for the gondola to rise as many meters as possible, calculating the work done by the applied force to elevate the system.

- Instructions:

• Divide into groups of up to 5 people.

• Build a 'gondola' using the provided materials: balloons, string, and small baskets.

• Set up the experiment in a long, straight corridor or area.

• Inflate a balloon and attach it to the gondola.

• Pull the balloon down the corridor, applying a constant force and recording the distance traveled by the gondola.

• Calculate the work done to elevate the gondola and discuss the factors that influence work, such as applied force and distance traveled.

Feedback

Duration: (10 - 15 minutes)

The purpose of this stage of the lesson plan is to consolidate learning through joint reflection. The group discussion allows students to verbalize and share their experiences, which helps solidify the knowledge gained. Additionally, by hearing their peers' perspectives, students can gain new ideas and insights, promoting a deeper and more applied understanding of the concept of work of a constant force.

Group Discussion

At the end of the activities, gather all groups for a group discussion. Start by asking each group to briefly present what they built and what they discovered about the work of a constant force. Then promote an exchange of ideas among the groups, encouraging them to share the challenges faced, the solutions found, and the lessons learned. This is an opportunity for students to articulate their knowledge and reflections while learning from each other.

Key Questions

1. What were the biggest challenges in applying the concept of work of a constant force in building your structures and how did you overcome them?

2. How did the distribution of force and the angle of force application affect the performance of the structures you built?

3. In what ways can what you learned today be applied in real situations or in other subjects?

Conclusion

Duration: (5 - 10 minutes)

The conclusion stage is crucial for ensuring that students have consolidated the knowledge acquired during the lesson. By summarizing and connecting theoretical content with practical activities, the teacher reinforces students' understanding and highlights the relevance of studying the work of a constant force. This final review helps prepare students to apply these concepts in future situations, both academic and professional.

Summary

At the conclusion of the lesson, the teacher should summarize the main concepts addressed, reinforcing the formula for the work of a constant force (T = F * d * cosθ) and how it was applied in practical activities. The teacher should also recap the problem situations discussed and how they were solved by the students.

Theory Connection

Explain how the practical activities, such as the Bridge Challenge, Cart Race, and Balloon Festival, helped connect theory with practice, allowing students to visualize and apply the concepts of work in real and hypothetical contexts. Highlight how the observation and direct manipulation of physical phenomena reinforce theoretical understanding.

Closing

Finally, highlight the importance of studying the work of a constant force in everyday life and in various practical applications, such as in structural engineering and the development of technologies. Emphasize how understanding this concept is fundamental for efficiency and safety in many industrial and daily processes.