A magnet can pick up iron, nickel, and cobalt using its strongest parts at the ends--the poles. With your class, you can make a temporary magnet using an iron nail and insulated wire. This is called an electromagnet. Below is a lesson plan to guide you as you teach the content and conduct the activity. I’ve provided a worksheet (pdf file) that offers a set of directions for your students to follow as they work in groups. The observations contain a T chart and a bar graph integrating math and science.
Students will be able to: create an electromagnet.
Teacher will hold up a large circular magnet with objects attracted around it. Teacher will show class and identify each item as they are pulled off. Teacher will hold up other items, such as: an AA battery; a safety pin; a nickle; a charm; a nail; a hook; a screw; an earning; a straight pin; and a paper clip.
Teacher asks, as s/he holds up new objects (such as a key, another safety pin, a D cell battery, a crayon, chalk), “By a show of hands, how many of you think this object will be attracted?” After a reinforcement of the fact that magnets only attract the metals iron, nickel, and cobalt, the teacher will test other objects that are on the teacher (jewelry) or that a student owns and wants to test.
Presentation of Content
Have students read vocabulary and instruct class to copy the words into their science notebooks.
Magnet - Attracts objects made of iron, nickel, and cobalt metal. It is strongest at its ends, called poles (north and south).
Electromagnet - A temporary magnet made with an iron nail and insulated wire. It can be turned on and off.
As students are copying, the teacher will inform them that their experiment worksheet is being passed out to each member of the group.
Observe and listen as the teacher refers children to the worksheet entitled “Electromagnet Experiment” and to the diagram on the board (redraw the diagram from the worksheet).
Observe and listen as teacher identifies the materials on each table’s tray: D cell battery; battery holder; [optional-battery holder; 2 battery clips or tape can be used to hold wire in place]; iron nail; cup filled with paper clips (materials can be purchased from local hardware store or from a science education company, such as Delta Education). Have students read directions as teacher demonstrates in front of the classroom:
- Place battery in the battery holder
- Put the battery clips in the battery holder with the silver clip part facing outward.
- Attach the stripped copper end of the insulated wire to the battery clip by pushing in the silver clip and holding it. Then slide the wire through.
- Wrap the insulated wire around the nail seven times. Attach the other end of the stripped wire to the other battery clip.
- You just made an electromagnet! Now, let’s see how strong it is by trying to attract paper clips to it. Write down the number of paper clips you attract in the right column. (Point to board.) Just try one paper clip. If your electromagnet is not able to pick it up, write the number 0 in the second column and move on to the next set of wire wraps.
- Repeat steps 4 and 5 for the remaining wire wraps- 14/ 21/ 28/ 35/ 42.
- You then take off one end of the wire from the battery clip and wrap the wire around seven more times and reattach the wire to the clip. Now try to pick up a paper clip. Once you’re able to pick up a paper clip, then try and pick up more than one by attaching them together first.
*Ask class if there are any questions on how to do the experiment or for the set up of the circuit.
The teacher will choose two material monitors to hand out one tray to each table. Inform class that they will work with the person next to them and arrange the class accordingly for anyone sitting by themselves. Teacher circulates the room to see that everyone understands and writes down their observations appropriately.
When the majority of the class is finished, the teacher will go over the number of attracted paper clips for each wire coil by asking for a show of hands for how many paper clips they picked up when their number is called.
Ask class the following questions to note understanding of the performed experiment (use a guide for the conclusion section of the worksheet).
- “How can you turn an object that is attracted to a magnet into an actual magnet?”
- “What was happening to the number of attracted paper clips as the number of wire wraps was increasing?”
- “What do you think would happen if I told you to create one electromagnet using two batteries?”
Questions or comments? E-mail me.