Magnetism

Magnetism is generated by moving

• protons.
• electrons.
• neutrons.
• elements.

What do the lines around this magnet represent?

• North Pole
• South Pole
• Magnetic Declination
• Magnetic Field

What is responsible for the Magnetic Field around Earth?

• The Earth's crust

• The Earth's molten iron core

• The Earth's mantel

• The Sun

An electromagnet's poles may be reversed by:

• decreasing the voltage of the coil
• increasing the number of coils
• changing the direction of current flow
• altering the material used to make the coils

What kind of magnet can be turned on and off?

• refridgerator magnet
• electromagnet
• magnetite
• iron

The strongest part of a magnet is...

• the bars.
• the force field.
• the poles. 
• the middle.

If a glass plate is placed over a magnet and iron filings are sprinkled over the glass, a pattern will be visible. What does this pattern indicate?

• The magnetic field

• The electrostatic field

• The piezoelectric effect

• The chemical reaction of the magnet and the filings

The needle of a compass points towards the north because...

• the Earth's magnetic south pole is situated near the Geographic North Pole.
• there is a battery inside the compass.
• The Earth attracts the south pole of the needle.
• There is a mass of iron inside the compass.

If you cut a magnet in half, what happens to the poles?

• One half gets the North Pole, the other half gets the South Pole
• Both halves get only a North Pole
• Both halves get only a South Pole
• Both halves get a North pole and a South Pole

How can a wire become magnetic?

• point it north

• add a resistor

• heat it up

• run a current through it