Extra 30 short questions and answers from Chapter:13 Fun with Magnets of Class 6 Science (CBSE):-
1. What is a magnet?
Answer: A magnet is a material that can attract iron and other magnetic substances. It has two poles, North and South, and shows magnetic properties.
2. What are natural magnets? Give an example.
Answer: Natural magnets are found in nature and have magnetic properties. Example: Lodestone (a naturally occurring magnetic rock).
3. What are artificial magnets? Give examples.
Answer: Artificial magnets are man-made magnets designed in different shapes. Examples: Bar magnet, Horseshoe magnet, Ring magnet, and Disc magnet.
4. Name two magnetic and two non-magnetic materials.
Answer:
Magnetic materials:
Iron, Cobalt.
Non-magnetic materials:
Plastic, Wood.
5. What are the two poles of a magnet?
Answer: The two poles of a magnet are North Pole (N) and South Pole (S). These are the strongest parts of the magnet where its force is the greatest.
6. What happens when two like poles of a magnet are brought close?
Answer: Like poles (North-North or South-South) repel each other.
7. What happens when two unlike poles of a magnet are brought close?
Answer: Unlike poles (North-South) attract each other.
8. What is meant by magnetic field?
Answer: A magnetic field is the area around a magnet where its force can be felt. It is strongest near the poles.
9. What happens if we cut a bar magnet into two pieces?
Answer: Each piece will still have a North and South pole because a magnet cannot have a single pole.
10. What are temporary and permanent magnets?
Answer:
Temporary magnets
: Lose their magnetism after some time (e.g., electromagnets).
Permanent magnets
: Retain their magnetism for a long time (e.g., bar magnets).
11. How can we magnetize an iron nail?
Answer: By repeatedly stroking it with a bar magnet in one direction, the iron nail becomes a temporary magnet.
12. What is a magnetic compass?
Answer: A magnetic compass is a device that shows directions using a freely suspended magnetized needle that always aligns in the North-South direction.
13. What is meant by the directive property of a magnet?
Answer: A freely suspended magnet always aligns in the North-South direction. This property is used in compasses.
14. Why does a magnet attract only some materials?
Answer: A magnet attracts only magnetic materials like iron, cobalt, and nickel because these materials allow the alignment of magnetic domains.
15. Why is the Earth considered a giant magnet?
Answer: The Earth has a magnetic field due to its iron and nickel core, causing compasses to align in the North-South direction.
16. What are electromagnets?
Answer: Electromagnets are temporary magnets made by passing electric current through a coil wrapped around an iron core.
17. What are the uses of magnets in daily life?
Answer: Magnets are used in electric motors, refrigerators, speakers, compasses, and MRI machines.
18. How does a magnet lose its properties?
Answer: A magnet loses its magnetism when it is heated, hammered, or dropped from a height.
19. Why are iron, nickel, and cobalt magnetic but not copper and aluminium?
Answer: Iron, nickel, and cobalt have magnetic domains that align in the presence of a magnet, whereas copper and aluminium do not.
20. What is a horseshoe magnet?
Answer: A horseshoe magnet is U-shaped and has strong magnetic power at its poles, making it useful in applications like electric motors.
21. What is a ring magnet?
Answer: A ring magnet is a circular magnet with a hole in the centre, commonly used in speakers and scientific experiments.
22. What happens when we sprinkle iron filings around a magnet?
Answer: The iron filings arrange themselves along magnetic field lines, showing the shape of the magnetic field.
23. How do we store magnets safely?
Answer:
Bar magnets should be stored
with keepers (iron plates) at both ends
.
Magnets should not be dropped or heated.
They should be stored away from other electronic devices.
24. Why are magnets used in cranes?
Answer: Powerful electromagnets in cranes lift heavy iron objects like cars and scrap metal in junkyards.
25. Why does a magnet not attract all metals?
Answer: Only ferromagnetic metals like iron, nickel, and cobalt are attracted because they have magnetic domains that respond to the magnetic field.
26. Why is a compass needle made of magnetized iron?
Answer: The magnetized needle in a compass aligns with the Earth's magnetic field, helping in navigation.
27. What happens when a magnet is kept near a television or computer screen?
Answer: It disturbs the display by affecting the electronic circuits inside, as screens are sensitive to magnetic fields.
28. What is the difference between a magnet and a magnetic material?
Answer:
A
magnet
produces a magnetic field and attracts certain materials.
A
magnetic material
(like iron) is attracted by a magnet but does not produce its own magnetic field.
29. Why are refrigerator doors lined with magnets?
Answer: The rubber strip inside the refrigerator door contains magnets that help it close tightly and prevent cool air from escaping.
30. How does a maglev train work?
Answer: Maglev trains use powerful electromagnets to lift and move the train without touching the track, reducing friction and increasing speed.
