Electricity and Magnets

4.0 A current in a wire makes an electromagnet

Fish

Try this: Fish for tacks or paper clips with a nail

 

What will happen if the nail is left out of the coil?

Does the nail keep its magnetism? (Try dropping it and retesting)

What will happen if you replace the nail with a brass screw?

Can brass be magnetized?

(Try replacing the nail with a large brass screw.)

What will happen if more batteries are used?

(Try doubling their number)

Continue the investigation by asking more questions of your own .

Predict an answer to your questions (Hypothesis)

Experiment to search for an answer.

[1] What will happen If ____________________________?

Hypothesis: ________________________________________________________________________________________________

[2] What will happen If ____________________________?

Hypothesis: ________________________________________________________________________________________________

[3] What will happen If ____________________________?

Hypothesis: ________________________________________________________________________________________________

4.10 The Strength of an Electromagnet

See diagram p159

 

 

Investigation by asking questions of your own .

Predict an answer to your questions (Hypothesis)

Experiment to search for an answer.

[1] What will happen If ____________________________?

Hypothesis: ________________________________________________________________________________________________

[2] What will happen If ____________________________?

Hypothesis: ________________________________________________________________________________________________

[3] What will happen If ____________________________?

Hypothesis: ________________________________________________________________________________________________

 

4.20 Electromagnets are used in the following:

.21 Electric Bell

Trace the circuit in the bell diagram.

(draw arrows on the conductors to show the electric current flow.)

Circle the switch in the bell.

Bell Diagram

 

.22 Electric Buzzer

Trace the circuit in the buzzer

(draw arrows on the conductors to show the electric current flow.)

Circle the switch in the bell.

 

Buzzer Diagram

 

 

 

.23 motors

Try This Motor; What fun!:

(Have fun playing with it until you get it to work)

Note: The tinplate, "U" must not contact the stiff wire, coil supports, as this shorts out the motor.

 

Try to simplify this motor:

Take away the tinplate "U"

Use only one magnet.

Use only one battery.

Can you get it to work? Try until you do.