What is a magnet?
that decorative magnets can be put on a refrigerator;
that magnets attract certain objects.
to describe magnetic interactions;
to name the magnetic poles of magnets;
to describe interactions between the poles of magnets;
to give examples of objects that are affected by magnets.
Magnetite
Objects are attracted thanks to interactions known as ‘magnetic’. We use magnetsmagnets, i.e., objects that have permanent magnetic properties, on a daily basis: in electric motors, bicycle dynamos, even on doors of lockers or when attaching tools.
How magnets interact with each other
The ends of magnets are called poles. Each magnet has two poles: the north one and the south one. On some magnets, these are marked with two colors (usually blue and red). Let's watch the video to see how the poles of magnets interact. We can also test this ourselves by conducting an experiment.
How do magnets interact with other objects?
The ancient Greek scholar, Thales of Miletus, noted that objects made of magnetite interact with objects that contain iron. Let's carry out a simple experiment to see which home objects are attracted by magnets.
Before you watch the movie „Magnet”, write down the research question and the hypothesis. Note your observations while watching the movie, and finally – note conclusions.
Film dostępny na portalu epodreczniki.pl
Film przedstawia eksperyment pokazujący jak działa magnes. W miseczce znajdują się opiłki żelaza. Przykładamy magnes na spód miseczki i obserwujemy jak przemieszczają się opiłki żelaza.
Magnetic field
Magnets affect not only other objects, but also each other. The space around a magnet, in which magnetic interactions (forces) occur, is called magnetic fieldmagnetic field.
What will happen if we try to divide one magnet into two? If we repeat the experiments on each of the pieces, we will see that there is a magnetic field around each of them. It turns out that two magnets were made from one. We are never able to obtain a single magnetic pole.
Magnetic poles in magnets are always in pairs.
Mark the correct statement about magnets.
- A magnet always has two poles called the north pole and the south pole.
- After sawing the magnet in half, we get two magnets. One has two north poles and the other has two south poles.
- A magnet can have one pole after it is sawed in half.
- A magnet can have three poles when one magnet attracts a half of another magnet.
Summary
Magnets produce a magnetic field.
In the area of the magnetic field, magnets act on certain objects with specific properties.
Each magnet has two poles. The same poles repel each other, and different poles attract each other.
At home, find devices that use magnets.
Keywords
magnet, magnetic field, poles
Glossary
pole magnetyczne – przestrzeń wokół ciał posiadających właściwości magnetyczne, w której występują oddziaływania magnetyczne
magnes – przedmiot posiadający trwałe właściwości magnetyczne