This can be a useful way of promoting discussion and debate, as well as helping to shape further teaching. Discussion about the forces on a stationary book sitting on a table, can lead to an understanding that the supporting force of the table on the book is balanced by a force downwards coming from the Earth.
By considering the same book as it topples from the edge of the table, discussion can now focus on the gravity force of the Earth pulling the book downwards. See the focus idea: Forces on stationary objects. Question Two — Pretend that the Earth is made of glass and you can look straight through it.
Which way would you look in a straight line to see people in far off countries like China or India? Imagine that a person holds a rock above the opening at the North Pole and drops it. Draw a line showing the entire path of the rock. Our website uses a free tool to translate into other languages. This tool is a guide and may not be accurate. The energy needed to pull the magnets apart comes from you, and you get it from the food you eat. And the plants or animals you eat get their energy from other plants and animals, or from the Sun.
All energy comes from somewhere. Hello, curious kids! Ask an adult to send your question to us. They can:. Please tell us your name, age and which city you live in. You can send an audio recording of your question too, if you want. Send as many questions as you like! Portsmouth Climate Festival — Portsmouth, Portsmouth. Similar magnetic poles repel and unlike magnetic poles attract each other.
At standards up to and including Level 3, it is appropriate to encourage students to observe and explore magnetic phenomena through play. Students should be encouraged to discriminate between magnetic forces, electrostatic and gravitational forces as being different to each other but examples of forces that can act without physical contact taking place i. Explore the relationships between ideas about magnetism and non contact forces in the Concept Development Maps — Electricity and Magnetism.
Provide students with a variety of different materials for them to investigate which ones have magnetic properties. These materials could include samples of: paper, plastic, polystyrene, wood, glass, rope, leaves, ceramic, rock, and some objects made of iron or steel.
Look to use only metallic objects made from iron or steel so students can see that being composed of a solid metallic material is a common property. Provide students with a bag of samples say and have them test the samples with a bar magnet or fridge magnet to see which ones are attracted to the magnet. Ask them to sort the objects into two separate groups: those that appear to be attracted to a magnet and those which do not.
Invite the students to offer suggestions of common features of the objects in the group that were attracted to the magnet. Is it their colour, weight or the substance they are made of that may make the difference?
Have students suggest and test their ideas to identify possible common properties. Next, ask students if all objects made of metallic materials are magnetic. Have any students had experiences which suggest otherwise? Now provide students with a number of objects made from different metals and ask them to sort the objects into two piles, predicting which objects will be attracted to a magnet and which will not. Some examples of metals and their sources could be: aluminium cans or foil, brass keys, copper nails or wire, steel screws or nails, zinc flashing or solder, iron bolts or nails, lead fishing sinkers and nickel welding rods.
After sorting the objects students can then test them to see if they have correctly predicted which materials are magnetic.
The intention here is to encourage students to test various materials and through investigation recognise that only a few metals have magnetic properties. An important point to be made is that in our everyday experience most metals appear to be magnetic because the most widely used metal is steel containing iron. This is made more difficult for students to explore because they must have at least two magnets of comparable strength and many of the familiar advertising fridge magnets used for simple investigations are weak and constructed in a way that they have no identifiable magnetic poles.
For example, closer you are to the Earth, stronger the force. Similarly, a magnet sets up a magnetic field in its surrounding space in which it magnetically affects any other magnetic material. The strength is represented by the density of the magnetic field lines. Magnetic field lines are closed curves leaving from North pole and entering the South pole when you follow them on the outside the magnet.
A compass, which is a small magnet itself, lines up parallel to the magnetic field lines at the point it is placed. The tip of the arrow is the North magnetic pole, and its end is the South magnetic pole. The building blocks of magnets are atoms, which are small tiny magnets. We will see later that, the motion of electrons moving electric charge is the fundamental reason of magnetism. For practical purposes we can focus on a cluster of atoms, called magnetic domains that are aligned in a specific direction.
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