These AP 6th Class Science Important Questions 10th Lesson Fun with Magnets will help students prepare well for the exams.
Fun with Magnets AP 6th Class Science 10th Lesson Important Questions and Answers
Very Short Answer Questions (2 Marks)
Question 1.
What is a magnet?
Answer:
A magnet is a metallic object which attracts iron or magnetic things made of iron, steel, nickel and cobalt.
Question 2.
When was magnetite discovered?
Answer:
Magnetite was discovered in 800 B.C.
Question 3.
What is the compound of a present in lodestone?
Answer:
Magnetite is the compound present in lodestone.
Question 4.
Your mother was repairing your shirt. The needle has slipped from her hand into a box containing buttons, threads, etc. How will you search for the needle?
Answer:
We will search for the needle with the help of a magnet. The magnet attracts the needle from the box containing buttons, threads, etc.
Question 5.
How many poles are there in a magnet?
Answer:
There are two poles in a magnet. They are: north-pole and south-pole.
Question 6.
Where is the maximum attraction in the magnets?
Answer:
Maximum attraction in the magnets is at the poles.
Question 7.
Which property of a magnet is used for the testing of permanent magnet?
Answer:
Repulsion property is used for the testing of permanent magnet.
Question 8.
In which direction does the suspended magnet come to rest?
Answer:
A magnet comes to rest in north-south direction.
Question 9.
What are magnetic materials?
Answer:
The materials that get attracted to a magnet are called magnetic materials.
Question 10.
Define magnetic poles.
Answer:
The ends of the magnets which contain most of their strength are called magnetic poles. A magnet has two poles i.e. North Pole and South Pole.
Question 11.
What will happen if a magnet is brought near a compass?
Answer:
The north pole of the compass attracts towards the south pole of a magnet.
Question 12.
When do two magnets attract each other?
Answer:
Two magnets attract each other when their unlike (opposite) poles come close to each other.
Question 13.
Name the instrument which is used to find the directions.
Answer:
Magnetic compass is used to find the directions.
Question 14.
Which method is used to convert an iron nail into a temporary magnet?
Answer:
Stroking is used to convert an iron nail into a temporary magnet.
Question 15.
Which magnet is used in an electric bell?
Answer:
In an electric bell, a U-shaped electromagnet is used.
Short Answer Questions (3 Marks)
Question 16.
What are the different types of magnets?
Answer:
There are two types of magnets. They are:
- Natural magnets: Magnets which are found naturally are called natural magnets.
Magnet the is the first known natural magnet. It is an ore of iron. Magnetite, Lodestone are examples of Natural Magnets. - Artificial magnets: Magnets which are made by humans is called artificial magnets.
Examples: bar magnet, horse-shoe magnet, cylindrical or a ball-ended magnet.
Question 17.
What are the main properties of a magnet?
Answer:
The main properties of magnet are:
- A magnet always has two poles i.e North Pole and South Pole.
- Poles of a magnet cannot be isolated
- Like poles repel and unlike poles attract each other
- A freely suspended magnet always get aligned to North-South direction
Question 18.
How can a magnet be demagnetised?
Answer:
Some of the methods to demagnetise a magnet are as follows:
- Heating a magnet to very high temperature
- Hammered or dropped from some height.
- Bringing the magnet in contact with the like poles of other magnets repeatedly.
- Passing the electric current through magnet.
Question 19.
If you are given two identical bars which look as if they might be made of iron. One of them is a magnet, while the other is a simple iron bar. How will you find out, which is which?
Answer:
We bring iron pins near both bars. The bar which attracts iron pins is the magnet. The bar which does not attract iron pins is a simple iron bar.
Question 20.
Why is it said that repulsion is a sure test for magnetism?
Answer:
Repulsion is a sure test for magnetism because to identify whether the given material is magnet or not, a magnet repulsion is the only way. This is because both poles of a magnet attracts an magnetic object but only two magnets can repel each other.
Question 21.
How does the magnetic compass work?
Answer:
A magnetic compass is basically a needle made up of a magnetic substance which responds (moves) in the presence of magnetic fields. When it is suspended freely, the north pole of the needle turns and points towards the north pole of the earth and vice versa.
Question 22.
How should we store magnets?
Answer:
We should store magnets by joining opposite poles of two magnets preferably with a piece of iron in between.
Question 23.
Which regions of the magnet are more attracted to iron filings?
Answer:
A bar magnet attracts more iron filings near its poles because the intensity of magnetic attraction is stronger near the poles.
Question 24.
What are differences between permanent and temporary magnets?
Answer:
Differences between permanent and temporary magnets are as follows:
| S.No. | Permanent Magnet | Temporary Magnet |
| 1. | The magnets that do not lose their property of magnetism even after a long period of time are called permanent magnets. | The magnets that lose their property- of magnetism after a short period of time are called temporary magnets. |
| 2. | It is made up of steel. | It is made up of soft iron. |
| 3. | It’s magnetism remains even if the source of magnetisation is remove. | Its magnetism is lost if source of magnetisation is removed. |
| 4. | It is a magnet for long period. | It is a magnet for a short period. |
Question 25.
Draw the diagrams of
Answer:
a) Bar magnet
b) Horse-shoe magnet
Question 26.
Do magnetic poles exist separately like charges? Explain.
Answer:
Magnetic poles do not exist separately like positive and negative charges. This means that it is not possible to isolate a north pole of a magnet from its south pole by cutting the magnet from the middle.
When we break a magnet from its middle, then we get two new magnets, each with its own north and south poles. This will continue indefinitely even if extremely small magnet is broken into two pieces, then they will have North and South poles, i.e, a small bar magnet is obtained. Thus, magnetic poles always exist in pairs.
Question 27.
What are the different shapes of magnets? Where are the poles located?
Answer:
Different types of magnets are :
- Bar magnet: The poles are located at the ends of the bar.
- Horse-shoe magnet: The poles are located at the two free ends of the ’U’ shape.
- Cylinder magnet: The poles are located at the two circular ends of the cylinder.
Question 28.
How do we store of magnet?
Answer:
Magnets lose their properties and become weak if they are not stored properly. To keep them safe, bar magnets should be kept in pairs with their unlike poles on the same side. They must be separated by a piece of wood while two pieces of soft iron should be placed between their ends. In the case of horse-shoe magnet, a single magnet keeper should be kept in such a way that it should touch both the poles of the magnet.
Question 29.
Differentiate between North pole and South pole of a magnet.
Answer:
Differences between North pole and South pole of a magnet are:
| S.No. | South Pole | North Pole |
| 1. | The end of the freely suspended magnet, which points towards the geographic south is called the south pole of the magnet. | The end of the freely suspended magnet, which points towards the geographic north is called the north pole of the magnet. |
| 2. | It is represented by S near its other end. | It is represented by N near its end. |
| 3. | It attracts the North pole of another magnet. | It attracts the South pole of another magnet. |
| 4. | Magnetic field lines end at the South pole outside the magnet. | Magnetic field lines emerge from the North pole outside the magnet. |
Long Answer Questions (5 Marks)
Question 30.
What is an electromagnet? Give two applications of electromagnets.
Answer:
An electromagnet is a type of magnet that is created by wrapping a wire coil around a ferromagnetic core and passing an electric current through the coil. The magnetic field produced by the current in the coil magnetizes the ferromagnetic core, making it magnetic.
Applications of electromagnet:
- They are used in electric bells, telephones, telegraphs, etc.
- They are used to separate magnetic substances like nickel, cobalt and iron from non-magnetic substances like brass, copper, zinc and plastics.
Question 31.
What are the uses of a magnets?
Answer:
The uses of magnet are :
- They are used to find the directions.
- They are used in audio and video tapes and computer hard disks to store information.
- They are used in dynamos, motors, loudspeakers, microphones etc.
- They are used in refrigerator door stickers, closing mechanism of refrigerators, doors, bulletin boards, and toys.
- They are used in toys to create magic effects.
- They are used in credit cards and ATM cards where the information is stored in a magnetic strip.
- Trains are pulled by the magnetic force that acts on the rails.
Question 32.
What are the differences between magnetic and non-magnetic materials.
Answer:
Differences between magnetic and non-magnetic materials are as follows:
| S.No. | Magnetic materials | Non-magnetic materials |
| 1. | Materials which get attracted towards the magnets are called magnetic materials. | Materials which do not get attracted towards the magnets are called nonmagnetic materials. |
| 2. | They are usually made of metals | They are usually not made up of metals. |
| 3. | They are used to make permanent magnets are the parts of operating systems where magnetic properties are required. | They are used to make parts of some operating systems where no magnetic effect is expected and other things such as cases of compasses. |
| 4. | They can be converted into magnets. | They cannot be converted into magnets. |
| 5. | Example: Steel, iron, nickel etc. | Example: Wood, plastic, fabrics etc. |
Question 33.
Name and describe the instrument that uses a magnet to find direction.
Answer:
The instrument that uses a magnet to find direction is a magnetic compass. This magnet consists of a magnetic needle pivoted at a point so that it can rotate freely. When a compass is kept at a place, the magnetic needle aligns in a north-south direction. We have to rotate it until the north of the needle matches the north of the scale.
Question 34.
What are the precautions should be taken while handling magnets ?
Answer:
Magnets should be handled with caution to avoid losing their magnetic properties. The following are some precautions to take when handling the magnets:
- Magnets should never be fired, hammered, or thrown from a great height.
- Magnets should be stored in pairs, with opposite poles facing each other.
- A piece of wood must be used to separate the magnets, with a piece of soft iron placed across their ends.
- A piece of iron should be kept across the poles of a horse-shoe magnet.
- We should keep magnets away from televisions, laptops, CDs, cassette tapes, mobile phones, and music systems.
Question 35.
Mention the properties of the poles of the magnet.
Answer:
The properties of the poles of a magnet are :
- A magnet always has two poles a north pole and a south pole.
- A freely suspended magnet always comes to rest in the north-south direction.
- Like poles of a magnet repel each other and unlike poles attract each other.
- The magnet’s poles are arranged in pairs, i.e. magnetic monopole doesn’t exist.
- Both the poles of a magnet have approximately same capacity to attract.
- Attraction! is maximum at the poles of a magnet.
It is because these points have maximum magnetic strength. On moving towards the centre, the magnetic power keeps on decreasing.
Question 36.
What do you mean by magnetisation?
Answer:
Magnetisation is defined as the process of creating an artificial magnet with the help of a magnet. To transform a non-magnetic material into a magnet, firstly, we must place the non-magnetic material, for example, an iron nail, on a table. Then move a strong magnet along the lengths of the iron nail without any disruptions. We must move the magnet in the same direction around 40-50 times until the iron nail becomes magnetised.
Case Based Questions (4 Marks)
Question 1.
Materials like nickel, cobalt and iron are called magnetic materials. These materials are attached to magnets. While materials like rubber, plastic, cloth, glasses etc., are not attracted to magnets and are referred to as non-magnetic materials. Ram placed his car on an aluminium sheet. He then placed a magnet under the aluminium sheet as shown in the figure.
The car must be made of magnetic material like iron or nickel. The moves along with the magnet, indicating that it must be aluminium sheet, not attracted, being the magnet allowed the car and the magnet to move freely. Due to magnet it is possible to move the car and magnet freely.
Now answer the following the questions:
a) What are non-magnetic materials?
Answer:
Materials like rubber, plastic, cloth, glasses etc., which are not attracted to magnets are referred to as non-magnetic materials.
b) What material is the car made of?
Answer:
The car is made of any of magnetic materials.
c) What does this activity tell us about aluminium?
Answer:
Aluminium is not attracted by a magnet. It is a type of material that indicating non-magnetic
d) How many poles does the magnet contain used by Ram?
Answer:
The magnet contains two poles.