Magnets, Field and Electromagnets Quiz

Magnetism is caused by ________________. 

• protons in the nucleus

• the motion of electric charges

• light waves striking certain rocks

• magic

All permanent magnets have two

• magnetic charges

• magnetic fields

• magnetic needles

• magnetic poles

Like poles on a permanent magnet will

• attract each other

• repel each other

• always interact

• point in the same direction

The magnetic field lines around a bar magnet

• are perfectly straight

• are only perpendicular to the magnet

• spread out from one pole and curve around to the other

• cross back and forth over one another

Which poles on the earth change?

• the North and South

• the magnetic poles

• the geographic poles

• the telephone poles

What makes an electromagnet different than a permanent magnet.....select all that apply

• it can be turned on and off

• it does not need any electricity

• its strength can be increased and decreased

• its polarity can be reversed

What type of materials are needed to create an electromagnet?

• battery, light bulb, plastic straw

• battery, coil of wire, iron core

• generator, iron core, switch

• switch, source of electricity, compass

What is the shape of a magnetic field around a wire?

• 
• 
• 
• 

Are the magnetic field lines in the picture correct?

• Yes, because they point from north to south.

• No, because they point from north to south (they're supposed to go the other way).

• Yes, because the North pole is on the left in all pictures.

• No, because the North pole is on the left in all pictures (it's supposed to be on the right).

The strongest part of a magnet is...

• the bars .

• the force field.

• the poles.

• the middle.