Lesson: Magnetic Fields Produced by Electric Currents

In this lesson, we will learn how to describe the magnetic field that is produced by a wire carrying an electric current.

Sample Question Videos

Q1:

For the magnetic field created around a current-carrying wire, the the current, the the magnetic field.

Q2:

Which of the following correctly describes what is meant by a “soft magnetic material”?

AA soft magnetic material is a material which loses its induced magnetism quickly.
BA soft magnetic material is a material which has a low density.
CA soft magnetic material is a material which loses its induced magnetism slowly.
DA soft magnetic material is a material which is relatively abundant in Earth’s crust.
EA soft magnetic material is a material which is both magnetic and highly malleable.

Q3:

Which two of the following are ways to increase the strength of the magnetic field created by a solenoid?

Q4:

Which of the following is the correct description of a solenoid?

AA solenoid is a single straight piece of wire. Passing an electric current along it creates a magnetic field around it.
BA solenoid is a long coil of insulated wire. Passing an electric current through it creates a magnetic field similar to that of a bar magnet.
CA solenoid is a single loop of insulated wire. Passing an electric current through it creates a magnetic field similar to that of a bar magnet.

Q5:

Which of the following correctly describes what is meant by a “hard magnetic material”?

AA hard magnetic material is a material which does not lose its induced magnetism easily.
BA hard magnetic material is a material which has a high density.
CA hard magnetic material is a material which loses its induced magnetism quickly.
DA hard magnetic material is a material which is magnetic and has a high melting point.
EA hard magnetic material is a material which is magnetic but not malleable.

Q6:

Which of the following materials would be a good material to use as the core of an electromagnet?

Q7:

Which of the four diagrams correctly shows the field lines of the magnetic field created around a current-carrying wire?

Preview