Electromagnetism

How do you make an electromagnet stronger?

• Add a motor and/or lightbulbs
• Add more light bulbs and/or wire coils
• add more wire coils and/or a switch
• add more wire coils and/or batteries

What is true about electricity and magnetic fields?

• Electricity is needed to create any magnet.
• Electricity always creates a magnetic field.
• Electricity is stronger than a magnetic field.
• Electricity prevents magnetic fields from occurring.

A coil of wire with an electric current in it is called a(n)

• A. transformer.
• B. electric generator.
• C. electric motor.
• D. solenoid.

What type of core is best for electromagnets?

• Steel

• Iron

• Plastic

• Copper

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).

When running a current through a wire, what do the blue lines represent?

• The wire spinning

• A magnetic field that was created

• Electrons leaving

• Electricity

If a current passes thru a coil of wire the coil of wire becomes a?

• A. monopole

• B. power source

• C.  solenoid

• D.  resistor

What would happen if I move a bar magnet in and out of a coil of copper wire?

• Electric current would decrease 

• The magnet would explode 
• Electric current will flow through the wire
• It would produce a gravitational field

The voltmeter is at 0 in this image. How would you manipulate the experiment to create a positive current?

(Negative on left and positive on right of voltmeter)

• Add more coils

• Reduce number of coils

• Push magnet in

• Flip magnet and push in

Can you produce current in a wire with a magnet that is sitting still?

• Yes; having a magnet near a wire is enough to excite the electrons

• Yes; if you use strong neodymium magnets

• No; magnets cannot create electricity

• Yes, but only if you move the wire relative to the magnet