Chapter 4: Exploring Magnets Worksheet
Chapter 4: Exploring Magnets
Worksheet
Section A – Multiple Choice Questions
1. Which of the following is a magnetic material?
(a) Wood
(b) Plastic
(c) Iron
(d) Glass
Answer: (c) Iron
2. Which of these is a naturally occurring magnet?
(a) Bar magnet
(b) Lodestone
(c) Ring magnet
(d) U-shaped magnet
Answer: (b) Lodestone
3. A magnet has how many poles?
(a) One
(b) Two
(c) Three
(d) Four
Answer: (b) Two
4. The two poles of a magnet are called:
(a) East and West
(b) Up and Down
(c) North and South
(d) Left and Right
Answer: (c) North and South
5. Where is the magnetic force of a bar magnet strongest?
(a) At the centre
(b) At the poles
(c) Everywhere equally
(d) Only on one side
Answer: (b) At the poles
6. Which materials are attracted towards a magnet?
(a) Magnetic materials
(b) Non-magnetic materials
(c) All materials
(d) Plastic materials
Answer: (a) Magnetic materials
7. What happens when two North poles are brought close together?
(a) They attract
(b) They repel
(c) They have no effect
(d) They melt
Answer: (b) They repel
8. What happens when the North pole of one magnet is brought near the South pole of another?
(a) Repulsion
(b) Attraction
(c) No interaction
(d) Both magnets lose their magnetism
Answer: (b) Attraction
9. A freely suspended magnet comes to rest in which direction?
(a) East-West
(b) North-South
(c) North-East
(d) South-West
Answer: (b) North-South
10. Which device is used to find directions?
(a) Thermometer
(b) Barometer
(c) Magnetic compass
(d) Measuring cylinder
Answer: (c) Magnetic compass
11. Which metal is magnetic?
(a) Copper
(b) Aluminium
(c) Iron
(d) Gold
Answer: (c) Iron
12. What happens if a magnet is broken into two pieces?
(a) One piece becomes North and the other South
(b) Both pieces lose magnetism
(c) Each piece has both North and South poles
(d) Only one piece remains magnetic
Answer: (c) Each piece has both North and South poles
13. Which of the following can be used to make a simple compass?
(a) Magnetised needle
(b) Plastic straw only
(c) Wooden stick
(d) Glass rod
Answer: (a) Magnetised needle
14. Which property helps us identify a magnet?
(a) Its colour
(b) Its weight
(c) Repulsion
(d) Its size
Answer: (c) Repulsion
15. Which of the following is a non-magnetic material?
(a) Nickel
(b) Cobalt
(c) Iron
(d) Plastic
Answer: (d) Plastic
Section B – Fill in the Blanks
1. A naturally occurring magnet is called a __________.
Answer: lodestone
2. A magnet has __________ poles.
Answer: two
3. The two poles of a magnet are called the __________ pole and __________ pole.
Answer: North, South
4. Materials attracted by a magnet are called __________ materials.
Answer: magnetic
5. Materials that are not attracted by a magnet are called __________ materials.
Answer: non-magnetic
6. Like poles of two magnets __________ each other.
Answer: repel
7. Unlike poles of two magnets __________ each other.
Answer: attract
8. A freely suspended magnet rests in the __________ direction.
Answer: North-South
9. A __________ is used to find directions.
Answer: magnetic compass
10. The magnetic force is strongest near the __________ of a magnet.
Answer: poles
Section C – Match the Following
Column A Column B
1. Iron (a) Finds directions
2. Magnetic compass (b) Non-magnetic material
3. Plastic (c) Magnetic material
4. North and North poles (d) Attract
5. North and South poles (e) Repel
Answers
1 – (c) Magnetic material
2 – (a) Finds directions
3 – (b) Non-magnetic material
4 – (e) Repel
5 – (d) Attract
Section D – True or False
1. Every magnet has a North pole and a South pole.
Answer: True
2. A single North pole can exist independently.
Answer: False
3. Iron is a magnetic material.
Answer: True
4. Plastic is attracted towards a magnet.
Answer: False
5. Like poles attract each other.
Answer: False
6. Unlike poles attract each other.
Answer: True
7. A freely suspended magnet points in the North-South direction.
Answer: True
8. Magnetic force is strongest at the centre of a bar magnet.
Answer: False
9. A magnetic compass contains a magnetised needle.
Answer: True
10. Breaking a magnet can produce a single North pole.
Answer: False
Section E – Very Short Answer Questions
1. What is a magnet?
Answer: A magnet is a material that attracts certain materials such as iron.
2. Name two magnetic materials.
Answer: Iron and nickel.
3. Name two non-magnetic materials.
Answer: Wood and plastic.
4. How many poles does a magnet have?
Answer: A magnet has two poles.
5. Name the two poles of a magnet.
Answer: North pole and South pole.
6. Where is the magnetic force strongest?
Answer: The magnetic force is strongest near the poles.
7. What happens between like poles?
Answer: Like poles repel each other.
8. What happens between unlike poles?
Answer: Unlike poles attract each other.
9. What is a magnetic compass?
Answer: A magnetic compass is a device used to find directions.
10. In which direction does a freely suspended magnet rest?
Answer: It rests in the North-South direction.
Section F – Short Answer Questions
1. What are magnetic and non-magnetic materials?
Answer:- Materials that are attracted towards a magnet are called magnetic materials, such as iron, nickel and cobalt. Materials that are not attracted towards a magnet are called non-magnetic materials, such as wood, plastic and glass.
2. Why are the ends of a magnet called its poles?
Answer:- The magnetic force is strongest near the ends of a magnet. These ends are therefore called the poles of the magnet. They are known as the North pole and South pole.
3. What happens when a magnet is broken into smaller pieces?
Answer:- When a magnet is broken into smaller pieces, each piece has both a North pole and a South pole. A single magnetic pole cannot be obtained.
4. Why does a freely suspended magnet point in the North-South direction?
Answer:- A freely suspended magnet points in the North-South direction because the Earth behaves like a giant magnet.
5. How does a magnetic compass work?
Answer:- A magnetic compass contains a magnetised needle that can rotate freely. The needle settles in the North-South direction and helps us identify different directions.
6. How can you distinguish a magnet from an iron bar?
Answer:- Bring the bars close to a known magnet. An iron bar is attracted by both poles. A magnet can show repulsion with a like pole. Therefore, repulsion can be used to identify a magnet.
7. Can magnetic force act through non-magnetic materials?
Answer:- Yes. Magnetic force can act through materials such as wood, cardboard, plastic and glass. Placing these materials between a magnet and a compass needle does not appreciably stop the magnetic effect.
Section G – Long Answer Questions
1. Explain the poles of a magnet and their properties.
Answer:- Every magnet has two poles: the North pole and the South pole. Magnetic force is strongest near these poles. Iron filings gather mainly around the poles of a magnet. The poles always occur in pairs. Even if a magnet is broken into smaller pieces, each piece has both North and South poles. Therefore, a single North or South pole cannot exist.
2. Explain the difference between magnetic and non-magnetic materials with examples.
Answer:- Materials that are attracted towards a magnet are called magnetic materials. Iron, nickel and cobalt are examples of magnetic materials.
Materials that are not attracted towards a magnet are called non-magnetic materials. Wood, plastic, glass and rubber are examples of non-magnetic materials.
Thus, magnets attract only certain types of materials and not all materials.
3. Explain attraction and repulsion between two magnets.
Answer:- When two magnets are brought close together, their poles interact.
- North pole + North pole → Repulsion
- South pole + South pole → Repulsion
- North pole + South pole → Attraction
Therefore, like poles repel each other and unlike poles attract each other.
Repulsion is an important property for identifying a magnet because an ordinary iron bar is attracted by both poles of a magnet.
4. How can a freely suspended magnet be used to find directions?
Answer:- A bar magnet can be suspended freely using a thread tied at its centre. When it is allowed to settle, it comes to rest in the North-South direction. The end pointing towards North is called the North pole, while the other end is the South pole.
This property of magnets is used in a magnetic compass to find directions.
5. Describe the construction and working of a magnetic compass.
Answer:- A magnetic compass is generally a small circular box containing a magnetised needle mounted on a pin. The needle can rotate freely. A dial below the needle has directions marked on it.
When the compass is placed at a location, the needle settles in the North-South direction. The marked directions on the dial can then be used to identify North, South, East and West.
6. How can you make a simple magnetic compass?
Answer:- A simple compass can be made using an iron needle, a bar magnet, a cork, a bowl and water.
First, magnetise the iron needle by repeatedly rubbing one pole of a bar magnet along the needle in the same direction. After sufficient rubbing, the needle becomes magnetised. Pass the needle through a cork and float it on water. The needle will rotate freely and finally settle in the North-South direction. Thus, a simple compass is ready.
7. Explain some important uses and precautions related to magnets.
Answer:- Uses of magnets:
- Finding directions using a magnetic compass.
- Closing pencil boxes and purses.
- Holding objects on magnetic boards.
- Moving steel objects without touching them.
- Making magnetic toys and other devices.
Precautions:
- Magnets should not be heated.
- They should not be dropped or hammered.
- They should be kept away from mobile phones and remote controls.
- Magnets should be stored properly to protect their magnetic properties.
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