Investigating the Magnetic Force Field: Calculating the Magnetic Pull of a Magnet by Varying Distances

Contributor
SERC: Science Education Resource Center at Carleton College Monjeau, Daryl
Type Category
Instructional Materials
Types
Experiment/Lab Activity , Lesson/Lesson Plan
Note
This resource, vetted by NSTA curators, is provided to teachers along with suggested modifications to make it more in line with the vision of the NGSS. While not considered to be “fully aligned,” the resources and expert recommendations provide teachers with concrete examples and expert guidance using the EQuIP rubric to adapted existing resources. Read more here.

Reviews

Description

Students will investigate the magnetic pull of a bar magnet at varying distances with the use of paper clips. Students will hypothesize, conduct the experiment, collect the data, and draw conclusions. As a class, students will then compare each team’s data and their interpretation of the results.

Intended Audience

Educator
Educational Level
  • Grade 3
  • Early Elementary
Language
English
Access Restrictions

Free access - The right to view and/or download material without financial, registration, or excessive advertising barriers.

Performance Expectations

3-PS2-3 Ask questions to determine cause and effect relationships of electric or magnetic interactions between two objects not in contact with each other.

Clarification Statement: Examples of an electric force could include the force on hair from an electrically charged balloon and the electrical forces between a charged rod and pieces of paper; examples of a magnetic force could include the force between two permanent magnets, the force between an electromagnet and steel paperclips, and the force exerted by one magnet versus the force exerted by two magnets. Examples of cause and effect relationships could include how the distance between objects affects strength of the force and how the orientation of magnets affects the direction of the magnetic force.

Assessment Boundary: Assessment is limited to forces produced by objects that can be manipulated by students, and electrical interactions are limited to static electricity.

This resource appears to be designed to build towards this performance expectation, though the resource developer has not explicitly stated so.

Comments about Including the Performance Expectation
In this experiment students will investigate how distance affects the amount of force a magnet is able to exert on a set of paper clips. The data will show that the closer the distance, the stronger the force as evidenced by the increasing number of clips the magnet is able to attract. Students should ask questions that demonstrate their understanding of the cause and effect relationships of the magnetic interactions.

Science and Engineering Practices

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
Students will conduct a simple investigation that will produce observational and measurement data. This data will serve as the basis for determining the cause and effect relationship of magnetic interactions between two objects that are not in contact with each other. Stop and ask: “What did you observe?” “What do you wonder?” This will encourage students to ask questions, one of which should be: “I wonder what would happen if you kept moving the magnet forward?” Through the implementation of an investigation to answer this question, students will gather data that will serve as the evidence of magnetic interactions between objects not in contact with each other.

This resource is explicitly designed to build towards this science and engineering practice.

Comments about Including the Science and Engineering Practice
Students will work collaboratively in teams to conduct a simple investigation that will produce observational and measurement data. This data will serve as the basis for determining the cause and effect relationship of magnetic interactions between two objects that are not in contact with each other. Some additional questions students should be guided to ask include: How could we design a “fair test” to see how distance affects the magnetic attraction? What should stay the same? (the number of clips tested, the type of clips) What will change? (the distance from the magnet) How will we record data? (make a table) As this lesson is targeted for third graders, the teacher guidance is suggested to develop the hypothesis based on their question, and to plan the experimental procedure. If students are not ready to develop hypotheses, students could make an initial claim instead. They could then investigate to find evidence to support whether the claim is valid or not.

Disciplinary Core Ideas

This resource is explicitly designed to build towards this disciplinary core idea.

Comments about Including the Disciplinary Core Idea
Through this experimentation students will clearly observe that magnets do not need to be in contact with objects to exert a force, and that the size of the force is dependent on their distance from the paper clips.

Crosscutting Concepts

This resource appears to be designed to build towards this crosscutting concept, though the resource developer has not explicitly stated so.

Comments about Including the Crosscutting Concept
It is important that students be able clearly articulate how distance affects the amount of force a magnet is able to exert on objects in their interpretation of the investigation results, and that they clearly use the terms cause and effect in their discussions.

Resource Quality

  • Alignment to the Dimensions of the NGSS: All dimensions are strongly addressed. Students will work collaboratively to conduct an investigation that will produce data. This data will provide the basis for evidence that distance affects the amount of force a magnet is able to exert on a set of objects (cause and effect relationship). Further, it will demonstrate that magnetic forces do not require that the objects be in contact, and that the size of the force depends on the properties of the objects and their distances apart.

  • Instructional Supports: This resource identifies key vocabulary, context for use and assessments. It provides for teaching notes and tips that are helpful, even for third graders who are still in the formative stages of conducting investigations. While this resource also provides for learning goals and key concepts, they are not clearly aligned to the investigation. It is suggested that the user of this resource focus on Learning Goal #2 and Key Concept #1.

  • Monitoring Student Progress: This resource recommends that the teacher record anecdotal information on the students as they conduct their investigation and as they respond during whole class discussions. It also recommends that the student’s thinking processes be evaluated through the science journal. However, as the hypothesis, procedure, data collection and conclusion are done as a class or with their teammates, this would only provide for limited formative assessment data. To assess students, a short constructed response assessing the student’s understanding of the cause and effect relationship of magnetic interactions between two objects not in contact with each other is suggested.

  • Quality of Technological Interactivity: - none -