Magnetic Fields

What can induce a magnetic field?

A.A current

B.Friction

C.Gravity

D.Work

A material that is naturally and permanently magnetic is called a ...

When magnetic field lines are denser at a certain point (like at the poles in the image), it means that the field is ... at that point.

A magnetic field is induced due the current flowing through a wire. In which direction should this current be flowing?

A.Up

B.Down

The Northern Light or "Aurora" is a beautiful phenomenon that happens at the poles of the Earth. What causes this effect?

A.The Earth's magnetic field that is so strong at the poles that is produces an electric field that ionizes the air molecules which gives the effect of the light.

B.Charged particles that come from the sun (=solar wind) that interfere with the Earth's magnetic field

C.It is an optical illusion due to the cold at the poles.

A current-carrying conductor is at right angles to a magnetic field. The force on the conductor is F. The conductor is turned so that it is parallel to the field with no other changes. In what way, if any, does the force on the conductor change?

An electron is entering a magnetic field. In which direction would the electron be pushed out of the field?

A.Left

B.Right

C.Up

D.Down

E.In the page

F.Out of the page