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Fun with Magnets – Class 6 Science Notes & Questions
Introduction: Magnets are simple yet powerful tools that help students observe invisible forces at work. This chapter explains what magnets are, how they behave, and how they are used in daily life. Below you will find clear, exam-friendly notes followed by a comprehensive set of questions and answers: 7 MCQs (with choices), 7 very short, 7 short and 7 long answer questions. Use the jump buttons above to move quickly between sections.
Notes: Key Concepts and Simple Explanations
What is a magnet?
A magnet is an object that attracts certain metals such as iron, nickel and cobalt. Natural magnets (like magnetite) occur in nature, while artificial magnets are manufactured in different shapes (bar, horseshoe, ring). Magnets show magnetic effects that can be measured and represented using magnetic field lines.
Magnetic poles
Every magnet has two ends called poles — the north pole and the south pole. These poles are where the magnetic force is strongest. Like poles repel each other (north repels north, south repels south), and unlike poles attract (north attracts south). The rule “like repel, unlike attract” helps us identify pole interactions.
Types of magnets
Common shapes include bar magnets, horseshoe magnets and ring magnets. Magnets may be permanent (retain magnetism) or temporary (show magnetism only in presence of a magnetic field or current). Electromagnets are a special type made by coiling a wire around an iron core and passing electric current.
Magnetic and non-magnetic materials
Materials such as iron, nickel, cobalt and steel are magnetic and get attracted to magnets. Materials like wood, plastic, glass and many metals such as copper and aluminum are non-magnetic and are not attracted. A simple classroom activity is to test small household objects with a magnet to classify them.
Magnetic field and field lines
The magnetic field is the region around a magnet where magnetic forces act. We draw magnetic field lines to show the pattern of the field: lines emerge from the north pole and enter the south pole. Field lines are denser where the magnetic field is stronger; they never cross each other.
Electromagnetism – basic idea
Electric current produces a magnetic effect. When current flows through a wire, it creates a magnetic field around the wire. Coiling the wire and placing an iron core inside it makes a strong electromagnet; switching the current on and off controls its magnetism.
Making and weakening magnets
A soft iron object becomes a temporary magnet when stroked with a magnet or put in a magnetic field. Permanent magnets can be made by heating and cooling certain metals under a magnetic field or by stroking them. Heat, strong hammering, or dropping magnets can weaken them because the ordered alignment of magnetic domains gets disturbed.
Everyday uses of magnets
Magnets are everywhere: fridge magnets, magnetic knots in bags, electric bells, loudspeakers, motors, compasses for navigation, and machines in industries. In medicine, strong magnets are used in MRI machines (for imaging). In recycling and scrapyards, powerful electromagnets separate metals from waste.
Simple safe classroom activities
Try these: test which objects are magnetic, find the poles of a magnet with another magnet, make a simple compass by magnetizing a needle and floating it on water, and sprinkle iron filings on paper over a magnet (under supervision) to reveal field patterns. Always clean up iron filings and keep small magnets out of reach of very young children.
Questions & Answers
Multiple Choice Questions (MCQs)
Q1. Which of the following materials is strongly attracted by a magnet?
- A. Plastic
- B. Iron
- C. Glass
- D. Wood
Answer: B. Iron
Q2. The end of a magnet that points towards the north when freely suspended is called the:
- A. South pole
- B. Neutral pole
- C. North pole
- D. Centre
Answer: C. North pole
Q3. Magnetic field lines are drawn from:
- A. South pole to north pole
- B. North pole to south pole
- C. Centre to poles
- D. They do not have direction
Answer: B. North pole to south pole
Q4. Which of these is a temporary magnet?
- A. Lodestone
- B. Steel nail kept near a magnet
- C. Permanent refrigerator magnet
- D. Magnetite
Answer: B. Steel nail kept near a magnet
Q5. Electromagnets are made by:
- A. Heating iron
- B. Rubbing iron
- C. Coiling wire around an iron core and passing current
- D. Cooling iron
Answer: C. Coiling wire around an iron core and passing current
Q6. Which of these will not be affected by a magnet?
- A. Paperclip
- B. Copper coin
- C. Safety pin
- D. Iron nail
Answer: B. Copper coin
Q7. Field lines are closest where the magnetic field is:
- A. Weak
- B. Strong
- C. Non-existent
- D. Same everywhere
Answer: B. Strong
Very Short Answer Questions (7)
Q1: Define a magnet.
Ans: An object that attracts iron, nickel, cobalt and some alloys.
Q2: Name two natural magnets.
Ans: Magnetite and lodestone.
Q3: Give one common use of a magnet at home.
Ans: Refrigerator magnets to hold notes or reminders.
Q4: What are magnetic poles?
Ans: The two ends of a magnet where its magnetic force is strongest, called north and south poles.
Q5: What do magnetic field lines show?
Ans: The shape and direction of the magnetic field around a magnet.
Q6: Which three metals are strongly magnetic?
Ans: Iron, nickel and cobalt.
Q7: How can you make a temporary magnet from a nail?
Ans: Stroke the nail several times in one direction with a bar magnet.
Short Answer Questions (7)
Q1: What happens when like poles of two magnets are brought close?
Ans: Like poles repel each other — they push each other away. You can show this by placing two bar magnets with like poles facing; they will move apart if friction is low.
Q2: Describe a simple activity to show magnetic field lines.
Ans: Place a bar magnet under a sheet of paper and sprinkle iron filings on top. Gently tap the paper so filings align along the field lines, forming curved lines from one pole to the other. This visual shows the pattern of the magnetic field.
Q3: What is an electromagnet and one use?
Ans: An electromagnet is a coil of wire wrapped around an iron core that becomes magnetic when electric current passes. It’s used in cranes at scrap yards to lift metal pieces and in electric bells.
Q4: Why does a compass point north?
Ans: A compass needle is a small magnet; it aligns with Earth’s magnetic field. The north-seeking end points approximately towards geographic north because of the Earth’s magnetic poles.
Q5: How does heating affect magnetism?
Ans: Heating disturbs the alignment of tiny magnetic domains in a magnet and can weaken its magnetic strength over time.
Q6: Name one industrial use of magnets.
Ans: Strong electromagnets lift heavy iron pieces in scrapyards and factories, making loading and sorting easier.
Q7: Explain why wood is not attracted by a magnet.
Ans: Wood is not magnetic because it lacks magnetic properties — its atoms do not align in a way that produces a magnetic effect like iron or nickel.
Long Answer Questions (7)
Q1: Explain how to identify the poles of an unknown bar magnet using a known magnet.
Ans: Take a magnet whose poles are known. Bring its north pole near one end of the unknown magnet. If they attract, that end is the south pole; if they repel, that end is the north pole. Repeat with the other end to label both poles. This method uses the principle that unlike poles attract while like poles repel.
Q2: Describe an experiment to show the magnetic effect of an electric current.
Ans: Place a compass near a straight wire connected to a battery through a switch. When the switch is closed and current flows, the compass needle deflects, showing a magnetic effect around the wire. Alternatively, wrap the wire around an iron nail and pass current to make an electromagnet that picks up small paper clips. This demonstrates that electric current produces magnetism.
Q3: Discuss the importance of magnets in daily life and technology.
Ans: Magnets are vital in daily life and industry. In homes they are used for closures and fridge magnets; in electronics they form parts of speakers, microphones, and hard disks; in healthcare, MRI machines use strong magnets for imaging; in industry, magnets power motors, generators, and lifting cranes. Their role in converting electrical energy to mechanical motion (and vice versa) makes them central to modern technology.
Q4: How can you make a simple compass at home and how does it work?
Ans: Magnetize a needle by stroking it with a magnet several times. Float the needle on a small piece of cork or boat of leaf in water. The needle will align with Earth’s magnetic field and point roughly north-south. The magnetized needle behaves like a small magnet with north and south ends and thus aligns with Earth’s field.
Q5: Compare permanent and temporary magnets with examples and uses.
Ans: Permanent magnets keep their magnetism over time (e.g., bar magnets, fridge magnets) and are used where constant magnetism is required. Temporary magnets (e.g., a steel nail stroked by a magnet) act magnetically only while in contact with a magnetic field or current. Electromagnets are controllable temporary magnets used where switching magnetism on/off is needed, such as in electric bells or industrial cranes.
Q6: Explain why iron filings form specific patterns around a magnet.
Ans: Iron filings become tiny temporary magnets in the presence of a magnetic field; each filing aligns along the local field. When many filings are sprinkled over paper above a magnet, they align along the invisible field lines, forming visible curved patterns from north to south. The pattern shows where the field is stronger (denser lines) and where it is weaker.
Q7: Design and explain a classroom activity to demonstrate repulsion between like poles of two magnets.
Ans: Place two bar magnets on a smooth table with like poles facing (north to north). Use a thin sheet of paper under one magnet to reduce friction. Slowly push them nearer and observe they push away. When released from close distance the magnets move apart. Record the distance at which repulsion is first noticed. The experiment shows like poles exert a repulsive force that increases as the distance decreases. This demonstrates the rule that like poles repel and the strength depends on distance.
Keep experimenting safely — magnets make invisible forces visible and learning fun!
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