Building a Solenoid

In the second make activity, students construct a solenoid consisting of a 3D printed tube and enameled copper wire. This activity can serve as a great introduction to computer-aided design (CAD) and computer-aided manufacturing (CAM). Students may design a 3D tube following design specification and fabricate the object using a 3D printer. Conversely, teachers or students can use the 3D model in the teacher guide to fabricate parts ahead of time. Regardless, students will use their solenoid to explore the properties of electromagnetism.

Materials

• Enameled Copper Wire (e.g., 32 AWG magnet wire)
• 3D Printed Solenoid (download here)
• Tape and/or Glue
• Enamel Remover (e.g., scissors, sand paper, or lighter)

Recommended

• Electric Winder
• 3D Printed Adapter (download here)

See Invention Kit Inventory for materials and sourcing information.

Step 1

Begin by placing the winder adapter on the winder, and then place the solenoid tube on the adapter.

Step 2

Begin by wrapping the wire around the solenoid tube several times. Make sure to leave a 10cm tail hanging off the tube. Apply a small amount of super glue to the wire and tube and let it set for a minute.

Step 3

Then wrap the 10cm tail up in a small coil and tape it on the side of the adapter. This will make the wrapping activity easier and prevent the tail from being wrapped around the coil.

Wrap the solenoid 1000 turns. The winder has a mechanical counter on the side that will show you the number of turns you have made. Try to wrap the coil as evenly as you can, as this will make a better solenoid. When you are finished wrapping, leave a 10cm tail on the end again, and apply a small amount of super glue over the entire coil wire. This will help keep everything in place, and prevent the wire from unspooling.

Building a Continuity Tester

In the first make activity, students construct a simple continuity tester consisting of a battery, an LED, and two insulated wires. Students learn how to solder electrical components together and can use this device to investigate the conductivity of different materials.

Materials

• Battery
• Battery Holder
• Battery Clip
• Soldering Iron
• Solder
• LED
• Insulated Wire
• Wire Strippers

See Invention Kit Inventory for materials and sourcing information

Step 1

Your first step is to identify how the batteries attach to the battery holder. Connect the batteries in the correct orientation. Attach the battery clip to the battery holder. Finally, strip away part of the insulation on the ends of the battery clip so that enough wire is exposed to attach an alligator clip to. 

Step 2

Take your LED and touch each leg to either end of the battery holder’s terminals. Does it light up? If not, flip the LED around and touch the legs to the battery terminal again. It should light up now.

This is orientation is very important. LED’s have a positive (+) and negative (-) leg, the positive is the longer of the two legs. The positive leg of the LED should attach to the red wire of the battery clip. The negative leg of the LED should attach to the black wire of the battery clip.        

Step 3

Wrap the red wire from the battery clip to the positive leg of the LED. This will make soldering the two parts together easier. 

Step 4

Soldering is an important skill for engineering. It allows us to make a strong electrical connection between two parts. You will use one hand to feed the solder and the other hand to melt the solder and flow it around the two parts. Soldering is an easy skill that anyone can pick up. You’ll be able to make all sorts of electronic projects once you learn this skill.

Turn on the soldering iron and wait while it heats up. In one hand, hold the solder (silver wire) and in the other hold the iron. Do not touch the tip or shaft of the iron. It is hot and will burn you. You will touch the tip of the iron to the metal terminal of the battery holder, wait several seconds while it heats up, and then slowly push the solder towards the metal terminal.

You should see the solder melt, and flow around the LED leg and metal terminal. Remove the solder iron, and place it back into the holder. The result should have a cone shape, almost like a Hersey Kiss. Trim the excess wire of the LED leg with the wire cutters.

Step 5

You should have a working continuity tester! To test it out, touch the black wire of the battery clip to the negative leg of the LED. It should light up when you touch them together. This indicates that the materials are conducting electricity. 

Step 6

Here is a photo of what the final continuity tester should look like. 

Invention Activity

Using your newly developed knowledge and skills with electricity and magnetism, your group must design and fabricate a Pop-up card. You have complete freedom in your design but it must be activated by an electromagnet. This means you cannot physically move the card with your hand in any way! You may use your pop up card from the first project if you wish.

Materials

You can make use of the following materials:

• Cardstock 
• Scissors 
• Silhouette Die Cutter
• Tape 
• Copper Wire 
• Copper Tape 
• Battery
• Iron coat hanger  
• LED lights

Design Drawing

Sketch a detailed drawing of how you plan to apply the science knowledge you learned from Labs 1-5 to construct your electromagnetically activated popup card.

Design Description

How will your card go from the “down” position to the “up” position without touching it? Your description should describe what you can see in the design drawing above.

Investigating Solenoids

The fifth lab activity is designed to facilitate the investigation of electromagnetism using solenoids. Students investigate how ferrous material (iron) and magnets interact with an electromagnet. Students draw conclusions based on what occurs when the orientation of the components and/or the battery is changed. Teachers should help students develop the fundamental understandings of electromagnetism so that they can apply this scientific knowledge to future engineering projects. As the five lab activities have built upon each other conceptually, this is an important final experience to promote student understanding.

Essential Question:

What are the relationships between solenoids and modern-day inventions?

Step 1

Remove a centimeter of the red insulation from each end of your solenoid. This ensures proper conductivity from the battery through the wire.

Take a piece of iron and place it inside the solenoid, leaving it hanging off the edge.

Connect both sides of the solenoid to the battery terminal.
What do you observe?

Animation 1

Step 2

Now take a permanent magnet from your previous experiments and place it halfway inside the solenoid tube.Connect both sides of solenoid to the battery.
What do you observe?
Can you explain what you observed?

Step 3

Now, flip the orientation of the solenoid wire connections to the battery.
What do you observe?
How does this compare to the previous step?

Animation 2

Exploring Electromagnetism

The fourth lab activity extends the detection of electromagnetic force to the study of solenoids. Students investigate how coiling the wire strengthens the magnetic field generated by the current carrying wire. Because solenoids are present in multiple FabNet Invention Kits, this lab activity is also a crucial experience in the instructional sequence.

Essential Question:

What are the properties of an electromagnet?

Materials

For this experiment, you will use the same materials as you used in the previous activity; a compass, 30cm piece of wire, and a 9V battery. 

Step 1

Begin by using the same piece of wire used in the previous activity. Make a small loop of wire, shown in the photo to the left.

Step 2

Place the loop of wire over the compass, just like in the previous activity. Connect the end of the wires up to the terminals of the battery. What do you observe? What happens if you change the orientation of the battery terminals?

Step 3

Now place the loop of wire under the compass, just like before in the previous activity. Repeat the same procedure of connecting the wires to the battery, and then changing the orientation of the battey terminals.

Step 4

Unwind the single loop and wrap the wire around the length of the compass several times. The wrap should be parallel with the North/South line on the compass. Leave enough length of wire on each side to connect up to the battery.

Step 5

Connect each end of the wire to the battery.

What do you observe?
How does this deflection compare to the deflection seen in previous experiments?

Step 6

Finally, change the orientation of the wire connections to the battery.
What do you observe?

Animation

Detecting Magnetic Fields

The third lab activity is designed to introduce students to the connection between electricity and magnetism. Students reenact Hans Oersted’s original discovery by placing a compass adjacent to a current carrying wire. This activity represents a crucial experience in the sequence of the FabNet Invention Kits as this discovery was used in many later inventions.

Essential Question:

What is the relationship between electricity and magnetism?

Materials

• battery
• battery clip
• magnet wire
• compass
• alligator clips
• lighter, scissors, or emery board

Step 1

Magnet wire is coated in a red enamel paint that insulates itself. Instead of using wire strippers, you can use a lighter to burn off the enamel coating. You do not need to hold the wire under the flame for very long – one second under the flame should remove the coating. Alternatively, you may use scissors or emery board to scratch the coating off. 

Expose enough wire to connect an alligator clip to each end of your magnet wire.

Step 2

Connect each end of the wire to the positive and negative battery terminals. Keep the battery at least six inches from the compass to avoid interference. Position the wire so that it is aligned with the north and south poles of the compass.

How does the wire affect the compass needle when the circuit is disconnected?

Step 3

Tap the alligator clip to the exposed end of the magnet wire. Do not leave this connected for more than a couple of seconds. The wire will get very hot and burn your hand if you are not careful. 

How does the wire affect the compass needle when the wire is connected to the battery?

Step 4

Now reverse the connections from the battery to the wires using the alligator clips. The battery has two terminals, one positive and one negative. Make sure you change the orientation from the previous step. Perform the same experiment as in the previous step. 

What do you observe? How is this different from what you observed in the previous step?

Step 5

Now place the wire under the compass. Connect the wire up to the battery in the original orientation (not reversed).Your circuit should look similar to the image on the left. Perform the same experiment as before.

How does the compass needle move when the wire is underneath the compass? How does this compare to when the wire was above the compass?

Step 6

Now reverse the connections from the wire to the battery, just like we did when the wire was above the compass.

What do you observe? How does this experiment compare to when the wire was above the compass? Can you think of an explanation for what you observed?

Investigating Conductivity

The second laboratory activity is designed to be a primary scaffold to understanding the fundamentals of conductivity, voltage, current, and resistance. Students construct a simple continuity tester consisting of a battery, an LED, and two insulated wires. Students learn how to solder electrical components together and can use this device to investigate the conductivity of different materials.

Essential Question:

What are the properties of electricity?

Materials

• continuity tester
• magnet
• wood
• copper
• iron

Step 1

Place the ends of tester on the material you are testing, and see if the LED lights up.

Step 2

The tester should light up when it makes contact with the copper. Copper is one of the most common conductive materials and can be found in many electronics.

Step 3

Now, use your continuity tester to determine what other materials conduct electricity. 

Investigating Magnetism

The first activity is designed to be a primary scaffold to understanding the fundamentals of permanent magnets: polarity, attraction, and repulsion. Students explore how various materials interact with a magnet and draw conclusions based on their observations.

Essential Question:

What are the properties of magnets?

Materials

• Permanent Magnet x 2
• Wood
• Copper
• Iron x 2

See Invention Kit Inventory for materials and sourcing information.

Step 1

Place the magnet beside the piece of wood. Now, flip the magnet. What do you see? What questions do you have?

Step 2

Place the magnet beside the piece of copper. Now, flip the magnet. What do you see? What questions do you have?

Step 3

Place the two iron rods next to each other. Move them around to see if they attract or repel each other. What do you see? What questions do you have?

Step 4

Place the magnet beside the piece of iron. What do you see? What questions to you have?

Try moving the magnet around the piece of iron, test what happens in different locations. What do you see? What questions do you have?

Step 5

Place the magnet beside another magnet? What do you see? What questions do you have?

Now turn one of the magnets around. What do you see? What questions do you have?