Print this chapterPrint this chapter

Module 4

1. Module 4

1.3. Lesson 1

Lesson 1

Module 4—Magnetic and Electric Fields in Nature and Technology

 

Lesson 1—Magnetic Fields

 

Get Focused

 

A photograph shows a compass on a map.

© RickParsons/shutterstock

A compass is a navigational tool for identifying directions on Earth’s surface. It consists of a tiny magnetized “needle” which is free to rotate around a fixed point in the centre. Being free to move, it will align itself with Earth’s magnetic field. This fact makes a compass a useful tool for understanding position and direction of motion relative to a common, fixed point, such as the geographic North Pole of Earth.

 

Another less known fact is what happens to a compass needle if you place it near a current-carrying wire. The needle will quickly swing around to a point perpendicular to the conductor. If the needle’s movement is a reaction to a current-carrying conductor, does that mean Earth is a giant conductor? How can Earth and a current-carrying conductor both have magnetic fields? What are magnetic fields and how are they produced?

 

In previous lessons you learned about gravitational fields and electric fields. In this lesson we will explore the magnetic field.

 

In this lesson you will answer the following essential questions:

  • What is a magnetic field?

  • How is Earth’s magnetic field produced?

  • What is the significance of a current-carrying conductor inducing a magnetic field?

Module 4: Lesson 1 Assignment

 

Your teacher-marked Module 4: Lesson 1 Assignment requires you to submit a response to the following questions:

  • Assignment—A 1, A 2, A 3, A 4, and A 5
  • Discuss—D 3

The other questions in this lesson are not marked by the teacher; however, you should still answer these questions. The Self-Check and Try This questions are placed in this lesson to help you review important information and build key concepts that may be applied in future lessons.

 

After a discussion with your teacher, you must decide what to do with the questions that are not part of your assignment. You should record the answers to all the questions in this lesson and place those answers in your course folder.