Teacher’s Guide
1
Magnetic poles
Learning objective: To understand how positive and negative magnetic poles can demonstrate push and pull forces.
1. List five objects that a magnet will attract.
LEVEL 1
Any metal objects. Not Aluminium. Examples: paperclip, metal ruler, metal spoon, a nail, a screw, a hammer etc.
2. What are the ends of a magnet called?
Poles. North and South Poles.
1. What type of metal will a magnet attach to?
LEVEL 2
Metals that contain Ferro (Iron).
2. What happens when alike poles of a magnet are placed close to each other?
They repel or push apart.
1. What type of metal will a magnet attach to?
Ferrous Metals. They contain iron.
LEVEL 3
2. What happens when alike poles of a magnet are placed close to each other?
What forces are produced?
They repel. Push forces are produced.
List and write the meaning of any key words you have learned.
Teacher’s Guide
2
Making a compass
Learning objective: To be able to make a compass and determine north and south poles.
1. Name two things in your school that face North from where you are standing / sitting now?
LEVEL 1
(Use a compass and find objects in the classroom or around the school that face North).
2. If you could stand at the North Pole – which end of the Earth’s magnet would you be standing on?
South Pole.
1. Name two things in your school that are in the direction North from where you are now.
If you move to another part of the school, will these things still be in the direction North of you?
LEVEL 2
(Use a compass and find objects in the classroom or around the school.
The bearing of the objects from your position will change as you move around the objects. This is because
the bearing North on the compass remains constant.
2. If you could stand at the North Pole – which end of the Earth’s magnet would you be standing on?
Can you explain why?
Because opposite poles attract, this definition means that the Earth's North Magnetic Pole is actually a
magnetic south pole.
1. Use the compass to help you face North and draw a plan of your classroom like a map.
LEVEL 3
2. Why do you think two spheres are used together to help make the compass.
The two spheres allow the compass points to rotate. They have a small contact surface and therefore little friction.
List and write the meaning of any key words you have learned.
Teacher’s Guide
3
Magnetic forces inside the spheres
Learning objective: To understand how to increase and decrease the push and pull magnetic forces inside the spheres.
1. What happens when you place two sets together each with a value of -2?
They repel or push.
LEVEL 1
-2
-2
2. What happens when you place two sets together, one with a value of +2 and the other with a
value of -2?
They attract or pull toghether.
+2
-2
1. What happens when you place two sets together each with a value of -2? Explain your answer.
LEVEL 2
-2
-2
They repel or push apart.
The spheres have the same sign and therefore push apart.
2. What happens when you place two sets together, one with a value of +2 and the other with a
value of -2? Explain your answer.
+2
-2
They attract or pull together.
The spheres have opposite signs and therefore pull together.
1. Write rules to explain what happens to the sets when they are placed close together with
spheres of different values?
LEVEL 3
If the spheres have same-signed charges (positive/positive or negative/negative) they will repel.
If the spheres have opposite-signed charges (positive/negative or negative/positive) they will attract.
If a sphere has no charge (value of zero) it will attract to both a positive or a negative charge.
2. What happens when a sphere with a value of zero touches another sphere with a value of zero?
As the spheres have no value and therefore no forces, the spheres neither attract nor repel.
List and write the meaning of any key words you have learned.
Teacher’s Guide
4
Magnetic Levitation
Learning objective: To understand that like poles repel and the meaning of magnetic levitation.
LEVEL 1
1. What is the distance between the levitating rods? Can you think of a way to measure this?
Explain below with a diagram.
Put two connected rods together and measure the height. Compare this with the height of the rods in the tube.
The difference is the distance of levitation.
1. What happens when you add more rods to the tube?
LEVEL 2
The distance of levitation increases.
2. What is the total distance of levitation with three rods?
Can you think of a way to measure this? Explain below with a diagram.
Put the three connected rods together and measure the height. Compare this with the height of the rods in
the tube. The difference is the distance of levitation.
1. When 3 or more rods are added, is the gap between each rod equal?
Can you devise a way to measure this and prove your theory? Explain below.
LEVEL 3
Compare the distance with two rods connected and then three. If the distance of levitation is more with
three rods then this shows that the distance of levitation increases as more rods are added.
2. Can you think of any practical uses for magnetic levitation or springs?
Soft close on doors and drawers (kitchens). Suspension.
List and write the meaning of any key words you have learned.
Teacher’s Guide
5
Accumulation of polarities
Learning objective: To understand the effects of increasing and decreasing the magnetic forces inside the spheres.
1. What happens when you place the two spheres close to each other?
They will attract or pull together.
LEVEL 1
-1
+4
1. What happens when you place the two spheres close to each other? Explain your answer.
They will attract or pull together.
LEVEL 2
-1
+4
2. Draw and label a similar set with just two spheres that would repel or demonstrate push forces.
The spheres must have same sign (positive/positive or negative/negative).
+1
+4
1. What happens when you place the two spheres close to each other? Explain your answer.
How would you increase or decrease the attraction between the spheres?
LEVEL 3
-1
+4
They will attract or pull together. The greater the difference in the values
between the two spheres the greater the attraction.
The smaller the difference the smaller the attraction.
2. How would you make two spheres repel with multiple rods? Draw your answer below with a
short explanation.
Like spheres will repel. The spheres must have the same sign. The higher or
lower the value, the greater the repelling push forces.
+4
+4
List and write the meaning of any key words you have learned.
Teacher’s Guide
6
Simple structures
Learning objective: To be able to form simple structures.
1. Explain why a square is a weak shape.
LEVEL 1
The joints on a square can easily flex and therefore distort the shape. It is not a fixed shape.
1. Explain why a triangle is a strong shape.
LEVEL 2
The joints on a triangle are fixed. It is a rigid shape. You cannot alter the shape.
1. Explain (with sketches) how to make a square into a much stronger shape.
LEVEL 3
This would strengthen the square but
the rods are not long enough.
A square based pyramid would strengthen
the square using the rods and spheres.
List and write the meaning of any key words you have learned.
Teacher’s Guide
7
Making regular polygons
Learning objective: To know what a regular polygon is and how to form a range of shapes.
1. Draw and label 3,4,5 and 6 sided regular polygons.
LEVEL 1
Equilateral Triangle
Square
Pentagon
Hexagon
1. Draw and label 3,4,5 and 6 sided regular polygons.
LEVEL 2
As above
2. Draw and label 3,4,5 and 6 sided irregular polygons.
Any 2d shape with the number of sides that may have different lengths and angles.
1. Draw and label 3,4,5 and 6 sided regular polygons. Add the internal angles for each shape.
LEVEL 3
Shape
Sides
Sum of Interior Angles
Shape
Triangle
3
180°
60°
Quadrilateral
4
360°
90°
Pentagon
5
540°
108°
Hexagon
6
720°
120°
List and write the meaning of any key words you have learned.
Each Angle
Teacher’s Guide
8
3-Dimensional (3D) structures
Learning objective: To understand how to form a structure using simple polygons.
1. Explain what a structure is?
LEVEL 1
A structure is a group of elements somehow united to support a load with stability.
1. Explain what a structure is?
LEVEL 2
(A structure is a group of elements somehow united to support a load with stability.
2. Draw a structure below. Label some simple shapes.
Example: A bridge. Triangles could be labelled. A house with squares and triangles.
1. Explain what a structure is?
A structure is a group of elements somehow united to support a load with stability.
LEVEL 3
2. The cube below is not a strong structure. How can you make this structure stronger?
Draw your ideas and explain why?
Bracing or forming triangles on the cube faces will make the cube more rigid.
List and write the meaning of any key words you have learned.
Teacher’s Guide
9
Complex 3D structures
Learning objective: To understand how to form 3D shapes.
1. Label and count the vertices, faces and edges on the cube below.
LEVEL 1
Vertices: 8
Faces: 6
Edges:12
1. Label and count the vertices, faces and edges on the triangular based pyramid below.
LEVEL 2
Vertices: 4
Faces: 4
Edges: 6
1. Draw, label and count the vertices, faces and edges on a hexagonal prism.
LEVEL 3
Vertices: 12
Faces: 8
Edges: 18
List and write the meaning of any key words you have learned.
Teacher’s Guide
10
Strong structures
Learning objective: To build a simple bridge structure and to understand how to make a structure stronger.
LEVEL 1
1. Draw the final bridge as a side view, clearly showing how you have strengthened the roadway
of the bridge.
1. Draw the final bridge as a side view, clearly showing how you have strengthened the roadway
of the bridge. Label any push or pull forces you can see.
LEVEL 2
1. Draw the final bridge as a side view, clearly showing how you have strengthened the roadway
of the bridge. Label at least two rods that are in ‘compression’ and two that are in ‘tension’.
LEVEL 3
Compression
Tension
List and write the meaning of any key words you have learned.
Teacher’s Guide
11
Truss bridges
Learning objective: To understand what a truss bridge is and the effect of triangulation on structures.
1. Draw a truss bridge below.
LEVEL 1
2. What is the most important shape in a truss bridge?
A triangle.
1. Draw a truss bridge below. Highlight a triangle.
LEVEL 2
2. Explain why triangles are so important?
A triangle is a rigid shape. Forming triangles will help add strength to the bridge and keep it rigid.
1. Draw a truss bridge below. Highlight a triangle.
LEVEL 3
2. What materials are used in the construction of truss bridges?
Steel is often used in the framework of a truss bridge. The steel beams can be bolted together to form
triangles and are relatively light compared to other materials such as concrete.
List and write the meaning of any key words you have learned.
Teacher’s Guide
12
Utilising push and pull forces
Learning objective: To build a structure to demonstrate magnetic push and pull forces.
1. Can you explain why the jaws will not close?
LEVEL 1
The tips of the jaws repel. The value of the top sphere is the same as the bottom sphere. Like poles will repel.
1. Can you explain why the jaws will not close?
LEVEL 2
The tips of the jaws repel. The value of the top sphere is the same as the bottom sphere. Like poles will repel.
2. How can you make the jaws shut with just one more rod? Draw your answer.
Attaching a rod to the top or bottom sphere with opposite polarity will lower the force of repulsion.
1. Explain, using the terminology you have learned, why the jaws will not close?
The jaws repel or push apart because the values of the spheres are the same and like poles repel or push apart.
LEVEL 3
2. How could you make the jaws open wider?
You would need to increase the value on the spheres by attaching more rods with the same polarity. This can
be done to either the upper or lower sphere or both. This would increase the magnetic force that will repel
or push and open the jaws wider.
List and write the meaning of any key words you have learned.
Teacher’s Guide
13
Oscillator
Learning objective: To understand how to utilise push forces to create an oscillating pendulum.
1. How long will the centre triangle oscillate? Time it using a stopwatch in seconds.
LEVEL 1
Pupils time the structure.
1. How long will the centre triangle oscillate? Time it using a stopwatch in seconds.
Pupils time the structure.
LEVEL 2
2. How do you think you can extend this time?
Reduce friction, try to extend the arc of oscillation by changing the size of the structure or the position of
repelling spheres.
1. Explain the term oscillation. Can you think of an object that oscillates?
LEVEL 3
A steady, uninterrupted, backward and forward swinging about a central point, a cycle of motion about a
central position. Pendulum of a grandfather clock, arm of a metronome...
2. On the diagram below, show the forces involved and the value of the magnetic forces on the
three top spheres.
-2 or +2
-3 or +3
-3 or +3
List and write the meaning of any key words you have learned.
Teacher’s Guide
14
Rotation and friction
Learning objective: Using spheres for low friction connections.
1. What happens to the bottom part when you spin the orange structure on the first model?
LEVEL 1
It too starts spinning.
2. What is causing it to slow down and stop in the end?
The spheres rubbing against each other. This is known as Friction.
1. Spin the two parts of the first model in opposite directions. What happens eventually?
LEVEL 2
The orange part will slow down. Then change direction to that of the lower part.
2. What is causing it to eventually slow down and stop?
The friction between the spheres.
1. Spinning the orange structure on the first model will make the bottom part spin too.
If you add more rods to strenghten the polarity on the top sphere, would that lessen or
strenghten the effect? Why?
LEVEL 3
Strenghten because the spheres would be pushed harder together.
2. Even if no friction existed at all between the spheres, the rotation would eventually stop anyway.
Why?
Air resistance on the rotating parts.
List and write the meaning of any key words you have learned.
Teacher’s Guide
15
Simple bearings
Learning objective: To understand how simple bearings work.
1. Explain why and how a simple bearing works.
LEVEL 1
Bearings reduce friction by providing smooth metal balls or rollers and a smooth inner and outer surface for
the balls to roll against. These balls or rollers "bear" the load, allowing the device to spin smoothly.
1. Explain why and how a simple bearing works.
LEVEL 2
As above.
2. Why is friction lower in a ball bearing?
The balls in a bearing roll rather than slide. When things slide, the friction between them causes a force that
slows them down. If the two surfaces can roll over each other, the friction is greatly reduced.
1. Draw and label the parts for a simple bearing.
LEVEL 3
2. What would happen to the movement of the structure if the coefficient of friction was zero?
It would continue forever and never slow down.
List and write the meaning of any key words you have learned.
Teacher’s Guide
16
Thrust bearings
Learning objective: To understand how a thrust bearing works.
1. What sort of loads are involved in a thrust bearing?
LEVEL 1
Axial loads. Loads in the direction of the shaft.
2. Would this bearing be suitable for a Merry-go-round? Why?
Yes. A Merry-go-round has vertical loads through the centre of
the rotation of the Merry-go-round.
1. What sort of loads are involved in a thrust bearing?
LEVEL 2
Axial loads. Loads in the direction of the shaft.
2. Draw on the direction of the axial load on the Merry-go-round below.
1. What sort of loads are involved in a thrust bearing?
Axial loads. Loads in the direction of the shaft.
LEVEL 3
2. Draw on the direction of the axial load on the Merry-go-round below.
Where else may you see thrust bearings?
Swivel chairs, excavator with turning cabin, construction crane.
List and write the meaning of any key words you have learned.
Teacher’s Guide
17
Adding rotational movement
Learning objective: To understand how to combine rotational movement with push and pull magnetic forces.
1. Describe what happens to the jaws when you rotate the centre part.
LEVEL 1
The jaws will open.
2. Show, using arrows, the rotational movement produced on the diagram below.
What magnetic force is experienced – push or pull?
A push force is produced as the
jaws open and repel.
1. Describe all the movement when you rotate the centre part.
LEVEL 2
The jaws open as the centre part is rotated. The value of the sphere at the tips of the jaws and the tip of the
rotating centre are all the same.
2. Show, using arrows, the rotational movement produced on the diagram below.
What magnet force is experienced – push or pull? How do you know?
A push force is produced because
the jaws open and repel.
1. Describe the movement and forces that are present when you rotate the centre part.
Explain why this happens.
LEVEL 3
A rotational movement is produced when you rotate the base. This causes the jaws to open as the spheres
of the base come close to the spheres of the jaws. The spheres repel causing a push force.
2. Show the rotational movement produced in the diagram below. What magnet force is
experienced – push or pull? How do you know?
A push force is produced because
the jaws open and repel.
List and write the meaning of any key words you have learned.
Teacher’s Guide
18
Driving movement
Learning objective:To understand how to create a driving movement using the magnetic push and pull forces. To create rotational
movement using simple bearings.
1. Describe the motion as you rotate the top section.
LEVEL 1
When the top section is rotated it produces an oscillating movement between the two sections but also
drives the bottom section to rotate due to push or repelling forces between the spheres.
2. Why is a bearing needed between the two sections?
To reduce friction between the two sections and allow movement to occur.
1. Describe the motion produced as you rotate the top section.
What magnetic force is causing the movement?
LEVEL 2
When the top section is rotated it produces an oscillating movement between the two sections but also
drives the bottom section to rotate due to push or repelling forces between the spheres.
2. Why is a bearing needed between the two sections?
To reduce friction between the two sections and allow movement to occur.
1. Explain why the two sections oscillate and rotate together?
LEVEL 3
When the top section is rotated it produces an oscillating movement between the two sections but also
drives the bottom section to rotate due to push or repelling forces between the spheres.
2. What would happen to the movement if there was no friction in the bearings? Is this possible?
If there was no friction then the structure would continue to move for longer. Only air resistance would slow
the movement. This is not possible as all touching surfaces produce some friction.
List and write the meaning of any key words you have learned.
Teacher’s Guide
19
Homopolar Magnetic Motor
Learning objective: To understand how a homopolar magnetic motor is made.
1. Draw and label the parts to a homopolar motor.
LEVEL 1
Battery
Copper Wire
Magnet
2. What is similar between this motor and a small electric motor found in toy cars?
The parts in the motors are the same. Each motor has a magnet and a copper wire and is powered by a battery.
1. Draw and label the parts to a homopolar motor.
LEVEL 2
See above.
2. What would happen if you used a battery with more power?
It would make the wire turn quicker.
1. Draw and label the parts to a homopolar motor.
See above.
LEVEL 3
2. What would make the wire turn quicker?
Increasing the power from the battery and increasing the magnetic force would make the wire turn quicker.
List and write the meaning of any key words you have learned.